Soil Characterization and Quaternary Pedology Laboratory

Lab Projects

Desert soils are characterized by unique spatial and vertical distribution of properties (e.g. texture, soluble salts, organic matter, surface cover) that are critical ecosystem processes. Distribution of these properties directly impacts surface stability and controls plant growth. Desert soil cover is complex consisting of a combination of desert pavement or gravel, inorganic and/or biologic soil crusts, and widely spaced desert shrubs. Natural growth and establishment of desert plants are largely limited by the availability of soil moisture. Ongoing studies in the Mojave and Sonoran Desert strongly indicate that overall characteristics of the soil, especially soil texture and structure, directly control the response of desert plants by controlling the flux of available soil water (McAuliffe and McDonald, 1995; Hamerlynck et al., 2000, 2002; McDonald, 2002; McDonald and Caldwell, 2003a, 2003b; Shafer et al., in press). The Soil Characterization Laboratory has the responsibility of measuring and reporting the data necessary for these on-going DRI projects.

Sample Projects

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Analysis of Desert Shrubs Along First-order Channels on Desert Piedmonts: Possible Indicators of Ecosystem Health and Historic Variation

PI: Eric McDonald

Funded bySERDP SEED Project #CS1153

Collaborators: Dr. Erik Hamerlynck (Rutgers University), Dr. Joseph McAuliffe (Desert Botanical Garden)

Keywords: desert shrubs, Desert Piedmonts

Project Description

The objectives of these projects are to develop critical knowledge about the relation between key soil processes, soil and surface water hydrology, and plant ecological dynamics common to desert piedmonts at the U.S. Army Yuma Proving Ground (YPG). Objectives are being met using a multidisciplinary approach, combining key aspects of the soil-water balance, historic background mortality of plants, ecophysiological measurements of living plants that are marginal to areas of plant mortality, and a the development of the basic soil-hydrological foundation connecting zones of mortality and living plants. The projects have five main objectives:

  1. Characterize fundamental physiochemical and hydrological processes of key desert soil areas critical to YPG
  2. Apply knowledge of soil processes to determine important linkages among soils, soil hydrology, and ecological dynamics.
  3. Evaluate if changes in soil and surface hydrology, due to both military activities and natural environmental variation, can be shown to predominantly account for changes in ecosystem health, especially the historic contraction of vegetation along the margins of alluvial fan surfaces.
  4. Determine historic range in variation of key desert vegetation common to alluvial fan surfaces and first-order rills.
  5. Provide recommendations that can be used to further develop and test methods or procedures that can be used to monitor ecosystem status and identify impacts related to natural disturbance relative to military activities

Much of the ephemeral water available for desert ecology appears to be derived from episodic surface runoff from alluvial surfaces; therefore, any change in surface runoff will directly correspond to changes in vegetation vitality along active washes. Vegetation along first-order drainages is likely to be impacted first by any natural or anthropogenic changes in the flux of surface runoff because these drainages are directly linked to surface runoff. Higher order channels may not be as sensitive to environmental change because as channel order increases, an increasingly larger contributing area and greater number of contributing channels supply runoff. An increase in likelihood of ephemeral runoff may result in a decrease in sensitivity to environmental change. If this hypothesis is true, then monitoring the ecology of selected first-order channels across both impacted and non-impacted drainage basins may provide an environmental “heads-up” about potential impact to downstream ecosystems due to a change in the supply of water from upland areas.

Basic Research Linkages Among the Soil-Hydrologic-Biologic Systems Common to the Desert Piedmonts, U.S. Army Yuma Proving Grounds

PI: Eric McDonald

Funded by: DoD EPSCoR Project 40983-EV-DPS

Collaborators: Dr. Erik Hamerlynck (Rutgers University), Dr. Joseph McAuliffe (Desert Botanical Garden)

Keywords: desert shrubs, Desert Piedmonts

Project Description

The objectives of these projects are to develop critical knowledge about the relation between key soil processes, soil and surface water hydrology, and plant ecological dynamics common to desert piedmonts at the U.S. Army Yuma Proving Ground (YPG). Objectives are being met using a multidisciplinary approach, combining key aspects of the soil-water balance, historic background mortality of plants, ecophysiological measurements of living plants that are marginal to areas of plant mortality, and a the development of the basic soil-hydrological foundation connecting zones of mortality and living plants. The projects have five main objectives:

  1. Characterize fundamental physiochemical and hydrological processes of key desert soil areas critical to YPG
  2. Apply knowledge of soil processes to determine important linkages among soils, soil hydrology, and ecological dynamics.
  3. Evaluate if changes in soil and surface hydrology, due to both military activities and natural environmental variation, can be shown to predominantly account for changes in ecosystem health, especially the historic contraction of vegetation along the margins of alluvial fan surfaces.
  4. Determine historic range in variation of key desert vegetation common to alluvial fan surfaces and first-order rills.
  5. Provide recommendations that can be used to further develop and test methods or procedures that can be used to monitor ecosystem status and identify impacts related to natural disturbance relative to military activities

Much of the ephemeral water available for desert ecology appears to be derived from episodic surface runoff from alluvial surfaces; therefore, any change in surface runoff will directly correspond to changes in vegetation vitality along active washes. Vegetation along first-order drainages is likely to be impacted first by any natural or anthropogenic changes in the flux of surface runoff because these drainages are directly linked to surface runoff. Higher order channels may not be as sensitive to environmental change because as channel order increases, an increasingly larger contributing area and greater number of contributing channels supply runoff. An increase in likelihood of ephemeral runoff may result in a decrease in sensitivity to environmental change. If this hypothesis is true, then monitoring the ecology of selected first-order channels across both impacted and non-impacted drainage basins may provide an environmental “heads-up” about potential impact to downstream ecosystems due to a change in the supply of water from upland areas.

Catalina Island Automated Climate Network

CO-PIs: Caldwell, Todd; McDonald, Eric; McCurdy, Greg

Funded by: Catalina Island Conservancy

Project period: 3/2004 – 8/2008

Real-time interactive web page: www.wrcc.dri.edu/catalina/

Keywords: Catalina Island, revegetation, radio network, soil-water balance

Project Description

Original funds provided in March 2004 by the Catalina Island Conservancy (CIC) and matched by DRI served as a pilot project to demonstrate the importance of climate, the soil-water balance of revegetation efforts, and monitoring of this unique island ecosystem. Results from this project are being used to develop the conceptual relationship between soil moisture, landscape position, and ecosystem condition. Furthermore, this data is helping to advance monitoring and restoration efforts of the island oak ecosystem.

Funds provided in Phase 2 and 3 by CIC have resulted in a total of 8 meteorological stations, including an island-wide radio frequency network.

Funds provided by Long Beach Unified School District in May 2008 added 2 additional meteorological stations including one at Avalon School and atop Dakin Peak. Both of these sites are located within the Falls Canyon Watershed where the Island Fire occurred from May 10-15, 2007 burning approximately 4,700 acres in the area northwest of the City of Avalon. These sites along with 3 mid-canyon soil moisture stations serve to monitor debris flow potential resulting from the fire.

Data is updated every 15-minutes and available through an automated, real-time interactive web page: www.wrcc.dri.edu/catalina

Catalogue of Analogs: Identifying Terrain Similarities between the World's Deserts and the US Army's Desert Hot Weather test site, Yuma Proving Ground YPG, southwestern Arizona

PI: Eric McDonald

Funded by: US Army Yuma PRoving Ground, Natural Environments Test Office

Project Team: Tom Bullard, Scott Bassett, and Steven Bacon

Keywords:World’s deserts, desert terrain, desert mapping

Project Description

The Department of Defense (DoD) is tasked with the challenge of testing military equipment and materiél under environmental conditions that best reflect operational field conditions. The Catalog of Analogs is part of an ongoing Desert Characterization study addressing comparability between the World’s deserts of potential military interest and available U.S. analogs, such as the U.S. Army’s Desert/Hot Weather test site, at the Yuma Proving Ground (YPG) in southwestern Arizona, U.S.A.

The scope of this catalog will include desert terrains of YPG and adjacent areas within the Sonora Desert and specific areas in other World’s deserts, including North Africa, Saudi Arabia, and the Middle East. This effort will provide the testers of military materiél, equipment, and systems with representative environmental conditions of the World’s deserts within which to test at YPG. The overall objectives are to better understand the effects of desert operations on the performance of military equipment and to improve the fidelity of desert testing of that equipment during materiél Research Development, Test and Evaluation (RDTAE) prior to deployment in the field.

Development

The characterization and mapping of the World’s deserts is being accomplished by the integration of:

  • Remote-sensing (satellite Landsat imagery)
  • Geographic Information Systems (GIS)
  • Photographic compilation of World’s deserts from low altitude and on-the-ground photographs
  • Compilation of World desert’s soils information

The characterization of the desert terrain includes the following geologic, geomorphic and geotechnical engineering elements:

  • Physiography
  • Geomorphic landforms
  • Soils
  • Surface materials

Products:

  • GIS and Remote-sensing based desert terrain maps of the World’s deserts at a variety of scales (e.g., 1:2,000,000 to 1:750,000)
  • Detail map of YPG desert terrain equivalents at a variety of scales (e.g., 1:120,000 to 1:5,000)
  • Text summary of World’s desert terrains and analysis of YPG
Geochemical and Physical Characteristics of Iraqi Dust and Soil Samples

PI: Eric McDonald, Todd Caldwell

Funded by: US Army Yuma PRoving Ground, Natural Environments Test Office

Collaborators:

  • Dr. Russell Harmon – Environmental Services Division Army Research Office
  • Mr. Graham Stullenbarger – U.S. Army Yuma Proving Ground-Natural Environments Test Office
  • Mr. Larry Havrilo – U.S. Army Yuma Proving Ground-Natural Environments Test Office
  • Mr. Dave Pond – U.S. Army Yuma Proving Ground-Yuma Test Center
  • Mr. Byron R. Cooper  U.S. Army Yuma Proving Ground-Yuma Test Center
  • Lt. Col. Dan Gilewatch, PhD – United States Military Academy-West Point
  • Col. Chris King, PhD – United States Military Academy-West Point
  • Dr. Lillian Wakely – Engineer Research and Development Center Geotechnical and Structures Laboratory
  • Ms. Julie Kelly – Engineer Research and Development Center Geotechnical and Structures Laboratory

Keywords: dust, weapon lubricant, Middle East, soil mechanics, YPG

Project Description

For the U.S. Army to operate successfully on a global scale, current and future troops as well as their equipment must be capable of accomplishing any mission in all possible environments: cold or hot, wet or dry, and every possible combination of terrain. This requirement challenges the Army’s equipment, people, and training programs. To prepare for a full spectrum of operations, the Army develops and tests its equipment under extreme environmental conditions to ensure that America’s soldiers have the best that science and technology can provide. Further, units conduct training in a realistic manner and in environments that simulate various natural settings. Finally, the Army must collect and analyze environmental data necessary to successfully plan for contingencies worldwide.

A particular and critical issue has evolved from U.S. combat experience in Iraq. Troops have reported that their individual combat weapons (M4 and M16 rifles) were jamming and failing to fire dependably. No specific causes were identified, but anecdotal information suggested that the problem was related to high levels of dust in the area combined with the properties of standard Army cleaner, lubricant, and preservative (CLP). Some troops had acquired commercially available gun lubricants that were reported to work better. An Army study (King et al., 2004) identified that dusts present in the world’s deserts vary greatly in physical and chemical properties, variables that have significant implications for military operations. This recent experience and knowledge has reinforced the importance of understanding the impacts of desert environments on military operations, especially in critical areas such as proper functioning of weapons.

Recognizing that weapons jamming could be related to physical and chemical properties of dust, the Desert Research Institute (DRI) was commissioned by the Army to undertake an analysis of a limited number of Iraqi dust samples collected during the period 27 March – 8 April 2004 by an onsite geologist of the U.S. Army Corps of Engineers. The purpose of this study is to describe the physical and chemical properties of sampled Iraqi dust, to analyze how this dust reacts with gun lubricants used in Iraq, and to develop recommendations for additional testing that would contribute to solving the gun-jamming problem for U.S. soldiers. This first-phase study is intended to provide a scientific basis for addressing dust-related aspects of the problem, not to provide a final solution.

Fifteen Iraqi dust samples were collected in total. Of these, nine were bulk surface soils collected at a variety of locations and were intended to capture some of the variability in dust sources based on the geology and geomorphology of the region. To evaluate potential differences between parent soils and resultant dust, six additional samples were taken inside tactical vehicles where weapons were stored or transported. All samples were analyzed to determine particle size, chemical composition, and reactivity of soil or dust components. Eight of the samples were tested to determine reactivity with three types of gun lubricants, including government stock CLP and two commercial products that troops found to work better than standard CLP. Analytical results describing physical and chemical properties of the Iraqi dust samples provide scientific guidance for the next steps in solving dust-related problems. The most critical findings from this study are:
  • Soils and dust collected from areas of military activity in Iraq differ significantly from the material used in chamber-testing procedures for weapons and are unlike natural geologic materials to which weapons are exposed during most training environments in the U.S.
  • The concentration of reactive chemicals, primarily salts and carbonates, is high in all Iraqi dust and soil samples and extremely high in many. Several of these reactive chemical components have the potential to corrode metal parts.
  • The average particle size of dust encountered in military operations in arid regions is much smaller than laboratory-generated quartz surrogate dust used in sand-and-dust chamber testing of weapons. Army experience has clearly shown that natural dusts have a significant impact on weapons operation and other mechanical equipment.
  • Laboratory testing has shown that three gun lubricants react with Iraqi dust, forming aggregates that increase the average size of particles in the sample. The extent of the reaction varies among dust samples with different chemical compositions and grain sizes. In general, dusts higher in salts and carbonates, and with smaller particles, are most reactive when mixed with the lubricants.>
  • The average particle size of dust taken from vehicles in Iraq was significantly smaller than the particle size of bulk soil samples. Further, the samples from vehicles had a higher concentration of reactive carbonates and sulfates. This reinforces that current chamber test methodology misrepresents real-world conditions.

Identifying the complete cause of gun-jamming problems experienced in Iraq must include testing with actual dust, or the equivalent, from the areas where the problems occurred. Differences in bulk soil samples compared with dust found in military vehicles operating in Iraq verify that operational considerations must be included in designing tests to evaluate and resolve this issue. Moving vehicles, and the weapons carried therein, act as natural dust traps for the smallest, and most potentially reactive, dust particles.

Given the importance of Iraqi dust in its potential to impact military equipment and operations, desert environmental parameters are critical to design tests that reflect real-world conditions-especially conditions most likely to compromise use of critical equipment in harsh desert environments. Previous work by King et al. (1999, 2004) demonstrated that each type of equipment test has a unique set of environmental conditions that are critical to the success of that test. Further analyses of the chemical properties of Iraqi dust are recommended to evaluate potential for corrosion and related impacts to military equipment.

This study quantified physical and chemical characteristics of dust derived from soils sampled in Iraq. This dust was found to be highly variable based on its origin and significantly different from the quartz materials used for standard chamber dust tests of military equipment. Further, the high concentrations of reactive chemicals and high volumes of fine clay materials were observed to react with chemicals found in gun lubricants.

Geochemical and Physical Characteristics of Vehicle Endurance and Dust Test Courses at U.S. Army Yuma Proving Ground

PI: Eric McDonald, Todd Caldwell

Funded by: US Army Yuma PRoving Ground, Natural Environments Test Office

Keywords:dust, vehicle testing, durability, soil mechanics, YPG, Sonoran

Project Description: U.S. Army Proving Ground (YPG) is DoD’s desert environmental test center. YPG has approximately 200 miles of unpaved endurance test courses of various severity levels and three dust test courses. Originally established in the 1950’s, there is concern that the endurance test courses may have worn down through the overlying desert strata to the extent that true desert conditions are no longer adequately represented.

Dust courses are established in areas of heavy underlying fine particulate layers and used for cyclic tests until depleted of dust by wind erosion from vehicle passes. The newest of the dust courses has had several years of use so there is the additional concern that these are also not representative of current operational areas in Southwest Asia.

This project is part of a subtask of an overall Desert Characterization Study addressing comparability between the World’s deserts of potential military interest and available U.S. analogs such as U.S. Army Proving Ground, Arizona. The overall objectives are to better understand the effects of desert operations on performance of military equipment and to improve the fidelity of desert testing of that equipment during material Research, Development, Test and Evaluation (RDTAE) prior to fielding.

This project is the first on a subtask related to gaining a better understanding of the distribution of dust, soils with potential of producing dust when disturbed, the effects of that dust on performance of military equipment, and improving dust testing methodologies. This particular study was constrained to sampling six of the “dustier” vehicle endurance test courses, current active dust courses (Kofa and Cibola Dust Courses) plus the older, currently inactive Muggins Mesa Dust Course. Sampling was restricted to potential dust producing environments along each test course. Course soil samples and soil samples taken in adjacent undisturbed areas were characterized for mineralogical, geochemical, and physical properties. Furthermore, dust collected from test vehicles (wheeled and tracked) covering this terrain was analyzed for dust characterization.

Global Military Operating Environments: Linking Natural Environments, International Security, and Military Operations (GMOE)

PI: Eric McDonald

Project period: 10/1/2008 – 09/30/2011

Funded by: DoD – Army Research Office

Project Description

The environmental conditions and parameters used in Ary testing of material and equipment should replicate the environmental conditions that are anticipated for areas where the U.S.Army will be deployed. In particular, extreme climatic and physical factors should be incorporated into live testing protocols to ensure functionality and sustainability of vehicles and weapons systems as well as enhancing battlefield technologies.

Initial studies to characterize the environments where U.S. forces are currently operating or will potentially operate have been in progress intermittently since 1998. The U.S. Army’s existing frameworks and approaches to characterize the natural environment worldwide are often outdated (most circa 1955-1980), oversimplifed, and lack integration of current scientific knowledge of critical processes that operate in global environments. Furthermore, current technology that can extensively characterize natural environments is underutilized. Science-based analysis of major global terrain environments is required to identify critical environmental variables that are the most likely to adversely impact military testing and tactical operations.

The overall scope of this multi-phase project is to characterize soil and terrain across all four major environmental systems (deserts, cold regions, tropics, temperate zones). Research activities will span comprehensive analyses of physical and chemical soil properties, with emphasis on the flux of mass and energy at the soil-atmosphere boundary. Results are critical to development and testing of technology for the identification and defeat of Improvised Explosive Devices (IEDs) through translation of surface to subsurface properties.

Specific Objectives

  1. Establish multiple Master Environmental Reference Sites (MERS) for comprehensive characterization of soil processes that represent common terrain conditions that are critical for military operations and testing.
  2. Initiate data analysis of the established MERS to evaluate temporal dynamics of energy fluxes under both natural and disturbed conditions in varying climatic conditions
  3. Explore techniques, methods, and results using near-surface processes that support development and testing of technologies for detection and defeat of IEDs
  4. Characterize terrain conditions at primary testing and training installations to determine terrain analogs with areas of current and future strategic interest
  5. Characterize general soil and terrain conditions for Afghanistan and other areas of strategic interest in CENTCOM
  6. Establish a military environments reference database that will collate soil and terrain data and related literature to increase availability of accurate global terrain data to the testing and training community
Integrated Desert Terrain Forecasting for Military Operations (DTF)

PI: Eric McDonald

Project period: 07/01/2003 – 06/30/2012

Funded by: DoD – Army, Robert Morris Acquisition Center

Project Description

Deserts are, and will continue to be, strategic sites for military operations. Military success in desert conditions requires familiarity with these environments, as well as appropriate training and testing in locations that are characterized by rapidly changing surface conditions and climatic extremes, ranging from dust storm and brownout generation to terrain-induced mobility and detection hazard.

The ultimate goal of this multi-year initiative is to develop an integrated, predictive tool for forecasting desert terrain conditions (soils, vegetation cover, landscape form, dust emission potential) to support military activities. Project results have lead to the development of a geographic information system (GIS) platform to predict essential surface and subsurface terrain conditions through the integration of data on the spatial distribution, age and geology of desert landforms. The GIS platform provides an expert-based prediction system, linking surface observables to subsurface conditions over a wide range of scales in near real-time by incorporating information from satellite and unmanned aerial remote-sensing technology.

Major Tasks

  • Predict terrain conditions through image analysis and inversion of geomorphic soil and landform models
  • Develop global database of critical soil and terrain features for accurate soil property predictions in a wide variety of landscapes
  • Acquire soil-surface data and improve technology to measure and model potential dust emission
  • Improve remote-sensing strategies for desert characterization
  • Continued advancement of integrated numerical models for production of rapid terrain characterization and visualization

Related Research sponsored in part by the Department of Defense

Bacon, S.N., McDonald, E.V., Baker, S.E., Caldwell, T.G., and Stullenbarger, G. 2008. Desert terrain characterization of landforms and surface materials within vehicle test courses at U.S. Army Yuma Proving Ground, USA. Journal of Terramechanics 45, 5, p. 167-183.

Berli, M., Caldwell, T.G., McDonald, E.V., and Gilewitch, D.A. In Press. Modeling desert pavement deterioration due to heavy vehicle traffic, Journal of Terramechanics.

Caldwell, T.G., McDonald, E.V., Bacon, S.N., Stullenbarger, G. 2008. The performance and sustainability of vehicle dust courses for military testing, Journal of Terramechanics 45, 6, p. 213-221.

Caldwell, T.G., McDonald, E.V. and Young, M. 2008. Soil disturbance and unsaturated hydraulic response at the U.S. Army National Training Center, Ft. Irwin, California. Journal of Arid Environments, 67, p. 456-472.

Dalldorf, G.K., McDonald, E.V., Bacon, S.N. and Nikolich, G. 2008. Testing and evaluation of a synthetic polymer for dust suppression in military applications. Geological Society of America Meeting, Oct. 5-10, Houston, TX.

Current Accomplishments

  • Continued effort toward global soil database population; current database coverage includes greater than 4,000 individual georeferenced pedological horizon descriptions
  • Successful testing of our GIS-based predictive mapping approach to rapidly map landforms and soils. First test effort mapped nearly 350 km2 in <20 staff=”” hours=”” li=””>
  • Advancement in understanding soil-landscape relations, across climatic gradients at Yuma Proving Ground, AZ, Death Valley, CA, and the Negev Desert, Israel
  • Characterization of mineralogy of dust-producing soils for assessment of dust impacts on military material and operations in Iraq
  • Development of Portable In-Situ Wind Erosion Lab (PI-SWERL) to measure dust emission from soil surfaces
  • Measurement of dust emission from desert surfaces by rotary-wing aircraft downwash, with computer visualizations of measured wind speeds and surface shear stresses
  • Modeling terrain-based hazards of desert surfaces to military operations – e.g. dust hazards for mobility, and deterioration of desert pavements – at both operational and tactical scales
  • Terrain Hazards Assessment: Global Physiographic, Salt Potential, and Dust Potential Maps – GIS Shapefiles
  • Pedohydrology of Desert Soils: extension of rapid terrain mapping techniques for regional flood assessment

Related Research sponsored in part by the Department of Defense

Engelbrecht, J., McDonald, E.V., Gillies, J.A., Gertler, A.W. In Press. Characterizing mineral dusts and other aerosols from the Middle East – Part 1: Ambient Sampling. Inhalation Toxicology.

Etymezian, V., Nikolich, G., Abonen, S., Pitchford, M., Sweeney, M., Gillies, J., and Kuhus, H. 2007. The Portable In-Situ Wind Erosion Laboratory (PI-SWERL): a new method to measure PM10 windblown dust properties and potential for emissions. Atmospheric Environment, 41, p. 3789-3796.

McDonald, E.V. and Caldwell, T.G. 2008. Geochemical characteristics of Iraqi dust and soil samples and related impacts to weapon malfunctions, p. 258-265. In: C.P. Nathanial, R.J. Abrahart, and R.P. Bradshaw (Eds.), Military Geography and Geology: History and Technology. Land Quality Press, Nottingham.

McDonald, E.V., Caldwell, T.G., Hamerlynck, E., and Morrill, V. 2006. Developing effective ecosystem monitoring strategies for military activities in deserts: results from the U.S. Army Yuma Proving Ground. ASA-CSSA-SSSA International Annual Meeting, Nov. 12-16, Indianapolis, IN.

DTF Highlight:
Global Physiographic Maps to Support Army Regulation (AR) 70-38

Maps developed in support of ongoing efforts to revise Army Regulation (AR) 70-38: Research, Development, Test and Evaluation of material for extreme climatic conditions. Maps provide multiple views of key global environments that enhance understanding of the types, global distribution, and potential hazards of conditions most likely to impact military operations.

DTF Highlight:
Regional Dust and Salt Concentration Maps
Air Force Research Laboratory Project in support of prevention of sand induced circuit card and electrical system corrosion

Products from this project are intended to advance understanding of the distribution and composition of airborne dust and sand. This dust and sand appears to be a major source of environmental contamination and corrosion of aircraft circuit boards. The primary initiative of this project – see map below – is the production of strategic-scale maps of potential dust and associated salt emission in southwest Asia. Emission estimates are derived from regional projections of soil type and content, based in part on work conducted at U.S. Army Yuma Proving Ground, Arizona, USA.

DTF Highlight:
Catalog of Analogs: Terrain Similarities between the U.S. Army Yuma Proving Ground and Central Southwest Asia

Catalog of Analogs employs the predictive methodology developed for the DTF program to identify similarities between deserts of potential military interest and deserts within the U.S. military lands. This project aims to improve desert material development and testing by identifying the best U.S. landscape analogs for international conflict areas. Initial comparisons were conducted at Yuma Proving Ground, Yuma, Arizona. Future work will expand this initiative to other U.S. military training and testing areas.

Integrated Site Design for the Restoration of Military Lands

Co-PIs: Eric McDonald, Todd Caldwell

Funded by: ITAM and the Natural Resources Support Team, Southwest Division Navy Facilities Engineering Command

Collaborators: Integrated Training Area Management (ITAM) San Diego State University, Soil Ecology and Restoration Group (SERG)

Project Description: One of the critical challenges of the Department of Defense (DoD) is maintaining sustainability of military installations while maximizing their use for military activities. To that end, the Integrated Training Area Management (ITAM) program was established to assess and quantify land conditions and develop strategies for rehabilitation.

In response to this need, the NTC-ITAM program established the following key objective “to incorporate the best available soil and hydrologic information at the project planning phase to enhance the effectiveness of rehabilitation efforts to better support sustainable training at NTC, Fort Irwin.”

Meeting this objective requires an integrated approach combining realistic characterization of essential soil physical and hydrologic attributes with Land Rehabilitation and Maintenance (LRAM) activities to increase the effectiveness of soil and plant restoration efforts.

Field investigations were conducted at two 10-acre rehabilitation sites (a geomorphically young and old soil surface) to document and map soil disturbance, plan restoration activities and evaluate restoration effectiveness. Soil disturbance polygons were identified and mapped within each site to delineate differences in disturbance level, soil type and texture, hydrologic characterization, vegetation density, and species composition. The site design was developed to evaluate restoration practices applicable to both the young and old surfaces using seven demonstration plots utilizing numerous techniques and irrigation treatments. Characterization data for each demonstration polygon was used to evaluate both surface treatments and irrigation strategies using a soil-water balance model.

LanDPro: Army Landscape Dynamics Support Program

PI: Thomas Bullard

Project Period: 06/15/2007 – 06/14/2010

Funded by: DoD – Army Research Office

Project Description: Meeting military readiness, mission capability, and battlefield preparation calls for large training areas in landscapes representative of the in-theater field environment. Access to safe and realistic training necessitates training area sustainability through land and cultural resource management, as well as the ability to predict and avoid areas sensitive to disturbance.

Cost-effective, system-wide methodologies based on integrated scientific approaches for rapid site assessment can minimize disruptions to training, while fulfilling management strategies.

LanDPro enhances and integrates recently completed soil, geomorphic, and hydrogeologic projects for ITAM and other DoD projects, as well as improves the robustness and universality of existing tools in support of land stewardship on DoD installations. The land manager will be able to use these tools to selectively assess and target sites for restoration and resource management. Additionally, expedited cultural resource inventories for DoD expansion areas or infrastructure modifications will be possible through enhancement of existing prototypes for predictive archaeological models.

Related Research Sponsored in part by the Department of Defense

McDonald, E.V., and Bullard, T.F. 2008. Geomorphic response to extreme change in a Mediterranean ecosystem: Holocene alluvial history of Santa Catalina Island, California, USA. European Geosciences Union, Geophysical Research Abstracts 10, EGU2008-A-10709.

McDonald, E., Bullard, T., Britt, T., and Ruiz, M. 2004. Development of an archaeological predictive model for management of military lands: identification of geological variables in desert terrain. In: D.R. Caldwell, J. Ehlen, and R.S. Harmon, Eds., Studies in Military Geology. Kluwer Academic, Boston, p. 259-270.

Predictive models

GIS-based archaeology predictive models incorporate a wide variety of spatial and environmental data, including site descriptions and classification, geology, geomorphology, soils, and hydrogeological data to produce favorability models for both site location and site preservation, and as decision making tools to help strategize and expedite cultural resource inventories.  LanDPro is working with cultural resources manages to incorporate soil-geomorphology into developing predictive models to enhance model capability strength and effectiveness.

Landscape Position and Hillslope Hydrology Associated with the Middle Ranch Hayfield Restoration

Co-PIs: Eric McDonald, Todd Caldwell, Thomas Bullard

Funded by: Catalina Island Conservancy and CALEM

Project Description: This is a collaborative effort with the Conservancy and serves as a pilot project to demonstrate the importance of assessing the soil water balance for the purposes of revegetation efforts and monitoring of this island ecosystem. Hydrologic characterization of both hillslope and valley bottom alluvial deposits is needed to develop both conceptual and numerical models for oak restoration work currently being conducted on Catalina Island, CA. Monitored soil microclimate indicates significant differences in available moisture between north- and south-facing slopes, and the valley bottom.

Soil moisture monitoring systems and a weather station were installed and operational as of 18 March 2004. The system consists of (1) a primary monitoring station that has an extensive combination soil moisture, soil temperature, and weather station sensors, and (2) 5 satellite soil moisture stations on both north and south facing hillslopes. The primary station was established to record key changes in soil moisture and temperature in the area of the Hayfield where oak restoration is currently being conducted. It also serves as a fully upgradeable base station for future additions of monitoring equipment or additional satellite stations. Each hillslope station is paired with a combination of sensors installed under an oak canopy and a second set in the adjacent interspace area. This design provides soil moisture and temperature data on soil beneath island scrub oak canopies and in the interspace areas.

DRI Home Master Environmental Reference Site (MERS): Deformation and recovery of desert pavements, U.S. Army Yuma Proving Ground

Co-PIs: Eric McDonald, Todd Caldwell, Steve Bacon

Funded by: U.S. Army Yuma Proving Ground, Natural Environments Test Office

Collaborators: Daniel A. Gilewitch (USMA), Mark Sweeney (USD)

Project Description: The Yuma Proving Ground (YPG) is a multi-purpose test facility within the U.S. Army Test and Evaluation Command covering more than 3,000 km2. It is located in 40 km north of Yuma, Arizona in the southwestern extent of the Sonoran Desert. Extensive areas of desert piedmonts (bajadas) at YPG have a nearly ubiquitous cover of well developed desert pavements that have formed on early Holocene to Pleistocene age alluvial deposits. Pavements consist of a single layer of surface stones that largely range in size from 1 to 5 cm and that form an armor of closely packed stones. The clasts have a well developed layer of rock varnish (patina) that forms the characteristic dark surface of these alluvial surfaces. Underlying the pavement is a gravel-poor and fine-textured vesicular (v) A horizon. This Av horizon is essentially an accretionary layer of dust that has accumulated below the surface layer of stones. Desert pavements are prominent features in arid and semi-arid environments and can be found on a variety of landforms. These types of stone covered soils are also commonly referred to as reg, hamada, gobi, and gibber plains. Specifically, the NRCS soil series is Cristobal-Gunsight, a loamy-skeletal, mixed, superactive, hyperthermic Typic Calciargids with a prismatic structure Av horizon from 0 to 8 cm, a fine granular Bw horizon from 8 to 15 cm, underlain by a gravel rich Ck horizon.

Under the auspices of the Army Research Office, the Natural Environment Testing Office at Yuma Proving Ground, in cooperation with the Desert Research Institute and the United States Military Academy, conducted research to expand the Army’s understanding of desert environments to better meet the needs of military equipment testing, soldier training, and unit operations (King et al., 2004). The study concluded that desert regions vary extensively in parameters important to the military mission, and that desert areas currently available for military testing, training and operations in the United States do not provide all the environmental conditions that troops and their equipment may encounter in potential conflict areas worldwide. In some cases, the physical training environment has been severely degraded to the extent that it no longer accurately represents the desired desert setting for testing and training. The study recommends, in part, that further analysis be conducted using desert Master Environmental Reference Sites (MERS) set aside to allow detailed data collection and analysis of desert environments over long periods of time. Analyses of MERS data can significantly enhance understanding of the long term sustainability of desert surfaces for military use.

To that end, the first MERS site was developed at YPG in June of 2006 to assess the degradation and recovery of a desert pavement following impacts from both tracked and wheeled military vehicles. Detailed measurements of soil compaction, hydraulic properties and dust emissivity were taken and will continue to be measured annually in an attempt to quantify both disturbance and recovery of these unique and ubiquitous desert soils.

Measuring Heterogeneities of Soil Hydraulic Properties from Canopy to Interspace

Co-PIs: Todd Caldwell, Michael Young, Robert Nowak

Project Period: 9/2006 – 7/2007

Funded by: NSF EPSCoR RING-TRUE III Grant Number 0447416

Project Description: The ecohydrology of arid environments is strongly coupled to amount and timing of available water. The surface soil structure and texture (presence/absence of fine-grained surfaces of dust accumulation or deeper restrictive soil layers of carbonate/clay deposits) affect the depth of water penetration and hence the diversity and vigor of native vegetation, rooting distributions, microbial activity and abundance, and biogeochemical processes that promote ecosystem health. Recent investigations have identified these linkages as being coupled between ecologic, hydrologic and pedologic processes, but uncertainty in the spatial heterogeneity of these linkages affects our ability to upscale or downscale the observed processes to other scales of interest: the bajada (large), the plot (medium), the point scale (fine). At the microsite scale (canopy or intercanopy), field investigations can yield point-scale information on particle size distribution and soil hydraulic properties, but relatively few have shown spatial patterns at the meter scale.

Obtaining hydraulic parameters in these heterogeneous soils is often tedious and field intensive. Soil texture or particle size distributions (PSD) are relatively easy to obtain, and have become common proxies for estimating hydraulic properties from pedo-transfer functions (PTF). These results can be obtained the laboratory using high-resolution laser-light scattering methods. Recent work by Meadows et al. (2006) at the Mojave Global Change Facility (MGCF) found spatial correlations for surface soil texture at approximately 50m for intercanopy locations. The resultant soil texture derived PTF resulted in highly variable Ks parameter field with a coefficient of variation of 0.47 and a spatial correlation length of 80m. The heterogeneity of the canopy/interspace distribution is likely to increase both the variability and spatial correlation of these hydraulic properties. The question that ultimately needs to be answered is whether wetting front variability in heterogeneous landscapes is generally dependent on the variability of flux at the upper boundary and less on the hydraulic property values.

We therefore seek to answer several questions that will directly tie into the SEPHAS project. From an ecohydrologic perspective, are highly heterogeneous properties influencing the soil-water balance of arid regions? From an experimental ecologist view, how vital is the spatial variability of hydraulic properties, either inferred or measured, to a random block experiment design, such as at the MGCF?

And how important is hydraulic property variability at the lysimeter scale, such as proposed by the SEPHAS project, where the soil-water balance can ultimately be determined?

The variability of hydraulic properties and its spatial relation to shrub and interspace will be determined using high-resolution measurements of Ks at 25-cm increments along transects radiating outward from a L. tridentata shrub to the interspace. Measurements will be made using a mini-tension infiltrometer array, which allows multiple point measurements to be conducted simultaneously and efficiently. Soil cores at each measurement site will be collected to obtain bulk density and soil texture from 0-10 cm depth. All resultant data will be explored for its spatial dependence and used to derive more site-specific hydraulic properties immediately surrounding the shrub site.

Remote Sensing for Mapping Near-Surface Playa Moisture

Co-PIs: Eric McDonald, Todd Caldwell, Don Sabol

Funded by: Army Research Office

Project Description: The relationship of near-surface moisture in desert playas to surface temperature is being studied for the purpose of using remote sensing to map subsurface moisture. This study is focused on two playas in the Mojave Desert of California: 1) a seasonally moist playa (Soda Lake Playa), and 2) a dry playa (Superior Playa). Detection and monitoring of near-surface moisture is important for understanding processes of desert landform evolution. Also, it is an important factor in determining trafficability and dust generation from vehicle operations.

Soda Lake Playa lies near the modern terminus of the Mojave River and can contain standing water in wet years. During drier periods (as during this study), the surface is dry with moist lake silts below. Hot dry weather drives capillary movement of water upward near the surface where it evaporates. In areas where this action is greatest (the western half of the playa) evaporite deposits (e.g. sodium carbonate, sodium bicarbonate) are formed. This is in sharp contrast to dry playas (Superior Playa) where the lake sediments are relatively dry to depths of 0.5 meters or more.

Field sites were established on each playa to sample the maximum variability of near-surface soil moisture and surface composition. At each site, thermocouples were imbedded in the soil at depths and data loggers were used to record temperatures at selected sites during satellite and/or aircraft overflights using airborne ASTER simulator data, and MASTER.

Radiant surface temperatures derived from the satellite and airborne image data were compared to field measured radiant temperatures and bulk surface temperatures (from thermocouples). These temperature profiles were then compared to soil moisture profiles. Day/night image data were used to produce an “apparent thermal inertia” image to identify areas of greatest sub-surface moisture. To confirm theses results, field-measured day/night temperature images were made of an area of the Soda Playa containing both moist and dry zones, using a hand-held FLIR camera.

Seedbed Microclimate: Modeling and Monitoring Soil Moisture in Support of the Restoration of Military Lands

PI/COPI: Todd Caldwell, Eric McDonald

Funded by: ITAM, Charis Corporation, Subcontract No. GS-012FG-A

Collaborators: Ruth Sparks and Matthew Hamilton, ITAM, Kent Osler, David Andersen, and Dennis Hansen, Bechtel-NV

Keywords: restoration, Mojave, vadose zone, soil moisture, modeling, hydrology

Project Description: The National Training Center (NTC), the Army’s primary mechanized maneuver training facility, covers approximately 2600 km2 within the Mojave Desert in southern California, is the subject of ongoing studies to support the sustainability of military lands in desert environments. Restoration of these lands by the Integrated Training Areas Management (ITAM) Program requires the identification of optimum growing conditions to reestablish desert vegetation from seed and seedling, especially with regard to the timing and abundance of plant-available water. The reestablishment and growth of desert plants is largely limited by the availability of soil moisture. Thus, a practical and economical methodology to estimate available soil-moist is needed to facilitate revegetation practices under the extremely arid conditions that typically prevail.

Seedbed microclimate; soil-water content, soil-water potential, and soil temperature, were continuously monitored and used to calibrate the Simultaneous Heat And Water (SHAW) and HYDRUS numerical models at 3, large scale, seeded restoration sites. Models were hierarchically parameterized to varying degrees of field data and modeling complexity to determine output validity. Various surface treatments including ripping, tackifiers, straw mulch, gravel mulch and plastic sheeting, and several irrigation scenarios were evaluated to determine effective restoration practices in order to maximize revegetation success and minimize water use.

Moderate site characterization and soil-water balance modeling can provide significant knowledge of seedbed microclimate, thus maximizing the benefits of irrigation applications. Soil-moisture can be manipulated to the appropriate depths and times to facilitate both seed germination and root establishment when revegetating Mojave Desert sites. Lastly, the benefits of common restoration practices (mulches and surface preparation) are dependent on both soil properties and seasonal timing.

Soil Evaluation in Support of Estimating Carrying Capacity and Landscape Degradation at the NTC Fort Irwin, CA

PI/COPI: Eric McDonald, Todd Caldwell

Funded by: ITAM, Charis Corporation, Subcontract No. GS-012FG-B

Project Description: The National Training Center (NTC) is the Army’s primary mechanized maneuver training facility, covering approximately 2,600 square km within the Mojave Desert in southern California. One of the greatest challenges to the Department of Defense (DoD) is maintaining the sustainability of military lands in desert environments while maximizing their use for military activities.

The goal of this project is to characterize changes in soil properties resulting from military activities under canopy and interspace locations. Military training exercises at the National Training Center (NTC), Ft. Irwin, California have led to the degradation of large areas of soil cover. Revegetation of these lands by the Integrated Training Areas Management (ITAM) Program requires identification of optimum growing conditions based on the character of the desert soil and the landscape position; hence land managers need a quantifiable measure of soil degradation.

The sampling approach is designed to evaluate important impacts to soil properties under various levels of disturbance or impact. Of primary consideration is the determination of soil parameters that are most affected by military training impacts and degradation of desert lands. This information is especially valuable for developing appropriate Land Rehabilitation and Maintenance (LRAM) strategies and interpreting Land Condition Trend Analysis (LCTA) data for the management of complex ecosystems and landscape dynamics in desert environments.

Results indicate that despite significant increases to bulk density following low and high disturbance, saturated conductivities were only modestly impacted. The soil morphology was highly impacted, particularly on older geomorphic surfaces. Desert pavements were stripped of their silt capped Av horizon and compacted by maneuvers, resulting in little overall change to the saturated conductivity but a large change soils.

Uranium Oxide Soil Stabilization Study, Yuma Proving Ground, AZ

PI: Michael Young

Funded by: Encapco LLC, Through the Navy Facilities Engineering Service Center, Port Hueneme, CA

Project Team: Vic Etyemezian, John Gillies, David Shafter, Eric McDonald, Steve Zitzer, and Todd Caldwell

Collaborators: Navy Facilities Engineering Research and Development Center (ERDC), Clemson University, Levine Fricke (LFR), US Army Corps of Engineers Engineering Research and Development Center (ERDC)

Project Description: The transport of radionuclides from contaminated soils can occur through several pathways including surface runoff, infiltration, and windblown dust transport. In cooperation with the Navy Facilities Engineering Service Center (NFESC), Encapco Technologies LLC is seeking to quantify the efficacy of a proprietary, organic-based emulsion treatment on the transport of radionuclides through the water transport pathway. The project field sites are divided into two locations. The first location is contaminated with depleted uranium; here, emulsion was added to the soil surface using a randomized block design using emulsion concentration and exposure time as variables. The second location is uncontaminated. Hydrological and ecological experiments are being performed on disturbed and undisturbed plots of different ages. The hydrologic experiments are focused on how infiltration and surface runoff potential might be impacted after the emulsion is applied to surface. Tests use tension infiltrometer and rainfall simulators for each plot, conducted quarterly. Ecological studies are focused on how the emulsion affects the germination rate and diversity of native seeds that have been exposed to the emulsion product.

Expected Results: Soils contaminated with depleted uranium or other radionuclides are difficult to remediate, and thus pose a long-term potential risk to the environment and humans. The affected areas may be wide spread, covering areas many square miles or more and conventional remediation techniques are too costly. In addition, the extraction of these contaminates from the soil matrix by physical or chemical methods of separation may result in further spread of contamination. The proper application of the Encapco emulsion represents a potential cost-effective method for remediation of these contaminated sites. The results are expected to identify (1) the concentrations needed to effectively complex DU on soil surfaces, and how the effectiveness changes with exposure time; (2) whether the product alters the hydraulic characteristics of the soil and if that poses a potential risk for surface runoff and erosion; and (3) if widespread application of the product might impact ecosystem function by altering the germination of native seeds.

CONTACT

Eric McDonald, Ph.D.
Lab Director
Eric.McDonald@dri.edu 
775.673.7430

Lab email: soils_lab@dri.edu
Lab phone: 775.673.7430
Contact Form

LAB LOCATION

Desert Research Institute
2215 Raggio Parkway
Reno, NV 89512

DIVISION

Earth & Ecosystem Sciences