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Regional Cost Estimates for Reclamation Practices on Arid and Semiarid Lands

Description: The U.S. Army uses the Integrated Training Area Management program for managing training land. One of the major objectives of the Integrated Training Area Management program has been to develop a method for estimating training land carrying capacity in a sustainable manner. The Army Training and Testing Area Carrying Capacity methodology measures training load in terms of Maneuver Impact Miles. One Maneuver Impact Mile is the equivalent impact of an M1A2 tank traveling one mile while participating in an armor battalion field training exercise. The Army Training and Testing Area Carrying Capacity methodology is also designed to predict land maintenance costs in terms of dollars per Maneuver Impact Mile. The overall cost factor is calculated using the historical cost of land maintenance practices and the effectiveness of controlling erosion. Because land maintenance costs and effectiveness are influenced by the characteristics of the land, Army Training and Testing Area Carrying Capacity cost factors must be developed for each ecological region of the country. Costs for land maintenance activities are presented here for the semiarid and arid regions of the United States. Five ecoregions are recognized, and average values for reclamation activities are presented. Because there are many variables that can influence costs, ranges for reclamation activities are also presented. Costs are broken down into six major categories: seedbed preparation, fertilization, seeding, planting, mulching, and supplemental erosion control. Costs for most land reclamation practices and materials varied widely within and between ecological provinces. Although regional cost patterns were evident for some practices, the patterns were not consistent between practices. For the purpose of estimating land reclamation costs for the Army Training and Testing Area Carrying Capacity methodology, it may be desirable to use the ''Combined Average'' of all provinces found in the last row of each table to estimate costs for arid ...
Date: February 1, 2002
Creator: Ostler, W. K.
Partner: UNT Libraries Government Documents Department

New Technologies to Reclaim Arid Lands User's Manual

Description: Approximately 70 percent of all U.S. military training lands are located in arid and semi-arid areas. Training activities in such areas frequently adversely affect vegetation, damaging plants and reducing the resilience of vegetation to recover once disturbed. Fugitive dust resulting from a loss of vegetation creates additional problems for human health, increasing accidents due to decreased visibility, and increasing maintenance costs for roads, vehicles, and equipment. Under conventional technologies to mitigate these impacts, it is estimated that up to 35 percent of revegetation projects in arid areas will fail due to unpredictable natural environmental conditions, such as drought, and reclamation techniques that were inadequate to restore vegetative cover in a timely and cost-effective manner. New reclamation and restoration techniques are needed in desert ranges to help mitigate the adverse effects of military training and other activities to arid-land environments. In 1999, a cooperative effort between the U.S. Department of Energy (DOE), the US. Department of Defense (DoD), and selected university scientists was undertaken to focus on mitigating military impacts in arid lands. As arid lands are impacted due to DoD and DOE activities, biological and soil resources are gradually lost and the habitat is altered. A conceptual model of that change in habitat quality is described for varying levels of disturbance in the Mojave Desert. As the habitat quality degrades and more biological and physical resources are lost from training areas, greater costs are required to return the land to sustainable levels. The purpose of this manual is to assist land managers in recognizing thresholds associated with habitat degradation and provide reclamation planning and techniques that can reduce the costs of mitigation for these impacted lands to ensure sustainable use of these lands. The importance of reclamation planning is described in this manual with suggestions about establishing project objectives, scheduling, ...
Date: October 1, 2002
Creator: Ostler, W. K.
Partner: UNT Libraries Government Documents Department

Range sustainability: Assessment and reclamation of arid plant communities and training area design for mission sustainability

Description: Seventy percent of US Department of Defense training and testing areas is on arid and semiarid land. Testing and training activities are often more devastating to arid lands than more mesic areas and, consequently, can threaten the continuation of military testing and training operations in these areas. Current gaps exist in diagnostic capabilities to distinguish among various degrees of sustainable and nonsustainable impacts from earth-disturbing activities in desert ecosystems. Work is ongoing to develop innovative remote sensing techniques to rapidly characterize impacts of military training and testing on arid environments. The diagnostic techniques include new rapid detection methods of image collection and laser induced fluorescence imagery techniques to provide early detection of the condition of stressed plants. Innovative image processing techniques will be assessed which will provide rapid assessment of vegetation parameters used in various US Department of Defense environmental management models such as the Army Training and Testing Area Carrying Capacity. New and cost-effective techniques for revegetation of disturbed training lands will be examined at Fort Irwin--the National Training Center in the Mojave Desert of California.
Date: December 1, 1999
Creator: Ostler, W. K.
Partner: UNT Libraries Government Documents Department

The effect of drought on four plant communities in the northern Mojave Desert

Description: Desert plant communities contain many perennial plant species that are well adapted to arid environments; therefore, one would intuitively believe that perennial desert species readily survive drought conditions. Abundant research on plant-soil-water relationships in North American deserts has shown that many species can maintain water uptake and growth when the soil-water potential is low. Little research, however, has focused on how prolonged drought conditions affect plant species in vegetation associations in desert ecosystems. A prolonged and widespread drought occurred in much of the western United States, including the Northern Mojave Desert, from 1987 through 1991. During this drought period vegetation characterization studies, initiated in 1990, by the US Department of Energy (DOE) at Yucca Mountain, Nevada, allowed EG and G Energy Measurements to collect data that could be used to infer how both desert vegetation associations and desert plant species reacted to a prolonged drought. This paper presents the preliminary results.
Date: December 31, 1993
Creator: Schultz, B.W. & Ostler, W.K.
Partner: UNT Libraries Government Documents Department

An evaluation of new high resolution image collection and processing techniques for estimating shrub cover and detecting landscape changes associated with military training in arid lands

Description: Research funded by the US Department of Defense, US Department of Energy, and the US Environmental Protection Agency as part of Project CS-1131 of the Strategic Environmental Research and Development Program evaluated novel techniques for collecting high-resolution images in the Mojave Desert using helicopters, helium-filled blimps, kites, and hand-held telescoping poles at heights from 1 to 150 meters. Several camera types, lens, films, and digital techniques were evaluated on the basis of their ability to correctly estimate canopy cover of shrubs. A high degree of accuracy was obtained with photo scales of 1:4,000 or larger and flatbed scanning rates from films or prints of 300 lines per inch or larger. Smaller scale images were of value in detecting retrospective changes in cover of large shrubs, but failed to detect smaller shrubs. Excellent results were obtained using inexpensive 35-millimeter cameras and new super-fine grain film such as Kodak's Royal Gold{trademark} (ASA 100) film or megapixel digital cameras. New image-processing software, such as SigmaScan Pro{trademark}, makes it possible to accurately measure areas up to 1 hectare in size for total cover and density in 10 minutes compared to several hours or days of field work. In photographs with scales of 1:1,000 and 1:2,000, it was possible to detect cover and density of up to four dominant shrub species. Canopy cover and other parameters such as width, length, feet diameter, and shape factors can be nearly instantaneously measured for each individual shrub yielding size distribution histograms and other statistical data on plant community structure. Use of the technique is being evaluated in a four-year study of military training impacts at Fort Irwin, California, and results compared with image processing using conventional aerial photography and satellite imagery, including the new 1-meter pixel IKONOS images. The technique is a valuable new emerging tool to accurately ...
Date: February 1, 2000
Creator: Hansen, D.J. & Ostler, W.K.
Partner: UNT Libraries Government Documents Department

An Evaluation of New High-Resolution Image Collection and Processing Techniques for Estimating Shrub Cover and Detecting Landscape Changes

Description: Research funded by the U.S. Department of Defense (DoD), U.S. Department of Energy (DOE), and the U.S. Environmental Protection Agency as part of the Strategic Environmental Research and Development Program (SERDP) evaluated novel techniques for collecting and processing high-resolution images in the Mojave Desert. Several camera types, lens, films, and digital processing techniques were evaluated on the basis of their ability to correctly estimate canopy cover of shrubs. A high degree of accuracy was obtained with photo scales of 1:1000 to 1:4000 and flatbed scanning rates from films or prints of 300 lines per inch or larger. Smaller scale images were of value in detecting retrospective changes in cover of large shrubs, but failed to detect smaller shrubs. New image-processing software, typically used in light microscopy, forensics, and industrial engineering, make it possible to accurately measure areas for total cover of up to four dominant shrub species in minutes compared to hours or days of field work. Canopy cover and individual shrub parameters such as width, length, circumference, and shape factors can be readily measured yielding size distribution histograms and other statistical data on plant community structure. These novel techniques are being evaluated in a four-year study of military training impacts at Fort Irwin, California. Results will be compared among the new and conventional imagery and processing, including 1-meter (m) pixel IKONOS images. The new processes create georectified color-coded contour maps of shrub cover for use with Geographic Information System (GIS) software. The technique is a valuable new emerging tool to accurately assess vegetation structure and landscape changes due to military or other land-use disturbances.
Date: May 1, 2001
Creator: Hansen, D.J. & Ostler, W.K.
Partner: UNT Libraries Government Documents Department

Biodiversity analysis of vegetation on the Nevada Test Site

Description: The Nevada Test Site (NTS), located in south-central Nevada, encompasses approximately 3,500 square kilometers and straddles two major North American deserts, Mojave and Great Basin. Transitional areas between the two desert types have been created by gradients in elevation, precipitation, temperature, and soils. From 1996 to 1998, more than 1,500 ecological landform units were sampled at the NTS for numerous biotic and abiotic parameters. The data provide a basis for spatial evaluations of biodiversity over landscape scales at the NTS. Biodiversity maps (species richness vs. species abundance) have been produced. Differences in biodiversity among ecoregions and vegetation alliances are presented. Spatial distribution maps of species' presence and abundance provide evidence of where transition zones occur and the resulting impact on biodiversity. The influences of abiotic factors, such as elevation, soil, and precipitation, on biodiversity are assessed.
Date: June 30, 2000
Creator: Ostler, W. K. & Hansen, D. J.
Partner: UNT Libraries Government Documents Department

Species and community response to above normal precipitation following prolonged drought in the northern Mojave Desert

Description: Little information is available on how desert plant communities that are dominated by perennial species respond to normal and above normal precipitation following prolonged drought. Intuitively, one would expect total canopy cover to increase. Whether a concomitant increase in the density of perennial species also occurs is unknown. Even less is known about how individual species respond to above normal precipitation following drought. From 1987 through 1991 a prolonged drought occurred in much of the western United States, including the northern Mojave Desert. In March 1991 the northern Mojave Desert received well above normal precipitation. The following two winters (December--March) also had above normal precipitation (150 to 200 % of normal, unpublished data). Ongoing vegetation characterization studies by the US Department of Energy (DOE) at Yucca Mountain, Nevada, allowed EG&G Energy Measurements to collect data that could be used to infer how both vegetation associations and individual species respond to above normal precipitation following prolonged drought. This paper reports the preliminary results.
Date: December 31, 1993
Creator: Schultz, B.W. & Ostler, W.K.
Partner: UNT Libraries Government Documents Department

Revegetation of Degraded Lands at U.S. Department of Energy and U.S. Department of Defense Installation: Strategies and Successes

Description: Recent research has provided important principles to follow in successfully revegetating disturbed lands in arid climates. Sustainable revegetation needs to be accomplished within the confines of the existing ecosystem of the area. Revegetation planning, revegetation implementation, and evaluation and monitoring should be considered for each revegetation project. Planning includes conducting a site assessment, establishing goals and standards, determining site preparation requirements, selecting species, selecting revegetation techniques, selecting conservation and water management treatments, determining timing and evaluating costs. Revegetation implementation begins with the selection of an on-site manager who will monitor adherence to the revegetation plan, conduct pre-job meetings and endure revegetation is implemented as planned. Project evaluation and long-term management includes conducting on-site inspections, evaluating success and implementing modification where necessary. Successful revegetation projects completed within the Great Basin and Mojave Desert ecoregions are presented. Seeding and transplanting prove to be successful in Great Basin ecoregion. Irrigation was used with highly predictable success in transition zone between Great Basin and Mojave Desert ecoregions. Seed pretreatment,irrigation, and various mulches show promise for successful revegetation in drier Mojave Desert ecoregion.
Date: January 1, 2002
Creator: Anderson, D. C. & Ostler, W. K.
Partner: UNT Libraries Government Documents Department

Land reclamation on the Nevada Test Site: A field tour

Description: An all-day tour to observe and land reclamation on the Nevada Test Site was conducted in conjunction with the 8th Wildland Shrub and Arid Land Restoration Symposium. Tour participants were introduced to the US Department of Energy reclamation programs for Yucca Mountain Site Characterization Project and Treatability Studies for Soil Media (TSSM) Project. The tour consisted of several stops that covered a variety of topics and studies including revegetation by seeding, topsoil stockpile stabilization, erosion control, shrub transplanting, shrub herbivory, irrigation, mulching, water harvesting, and weather monitoring.
Date: December 31, 1993
Creator: Winkel, V.K. & Ostler, W.K.
Partner: UNT Libraries Government Documents Department

Biodiversity Analysis of Vegetation on the Nevada Test Site

Description: The Nevada Test Site (NTS) located in south central Nevada encompasses approximately 3,561 square kilometers and straddles two major North American deserts, Mojave and Great Basin. Transitional areas between the two desert types have been created by gradients in elevation, precipitation, temperature, and soils. From 1996-1998, more than 1,500 ecological landform units were sampled at the NTS for numerous biotic and abiotic parameters. These data provide a basis for spatial evaluations of biodiversity over landscape scales at the NTS. Species diversity maps (species richness vs. species abundance) have been produced. Differences in ecosystem diversity at the ecoregion, alliance, association, and ecological landform unit levels are presented. Spatial distribution maps of species presence and abundance provide evidence of where transition zones occur and the resulting impact on biodiversity. The influences of abiotic factors (elevation, soil, precipitation) and anthropogenic disturbance on biodiversity are assessed.
Date: June 1, 2001
Creator: Ostler, W. K. & Hansen, D. J.
Partner: UNT Libraries Government Documents Department

Vegetation Change Analysis User's Manual

Description: Approximately 70 percent of all U.S. military training lands are located in arid and semi-arid areas. Training activities in such areas frequently adversely affect vegetation, damaging plants and reducing the resilience of vegetation to recover once disturbed. Fugitive dust resulting from a loss of vegetation creates additional problems for human health, increasing accidents due to decreased visibility, and increasing maintenance costs for roads, vehicles, and equipment. Diagnostic techniques are needed to identify thresholds of sustainable military use. A cooperative effort among U.S. Department of Energy, U.S. Department of Defense, and selected university scientists was undertaken to focus on developing new techniques for monitoring and mitigating military impacts in arid lands. This manual focuses on the development of new monitoring techniques that have been implemented at Fort Irwin, California. New mitigation techniques are described in a separate companion manual. This User's Manual is designed to address diagnostic capabilities needed to distinguish between various degrees of sustainable and nonsustainable impacts due to military training and testing and habitat-disturbing activities in desert ecosystems. Techniques described here focus on the use of high-resolution imagery and the application of image-processing techniques developed primarily for medical research. A discussion is provided about the measurement of plant biomass and shrub canopy cover in arid. lands using conventional methods. Both semiquantitative methods and quantitative methods are discussed and reference to current literature is provided. A background about the use of digital imagery to measure vegetation is presented.
Date: October 2002
Creator: Hansen, D. J. & Ostler, W. K.
Partner: UNT Libraries Government Documents Department

Plant-Damage Assessment Technique for Evaluating Military Vehicular Impacts to Vegetation in the Mojave Desert

Description: A new plant damage assessment technique was developed by plant ecologists from Bechtel Nevada at the U.S. Department of Energy's National Security Administration Nevada Operations Office and funded by the Strategic Environmental Research and Development Program Project CS-1131 in cooperation with the U.S. Army's National Training Center (NTC) at Fort Irwin, California. The technique establishes linear transects the width of vehicle tracts from evidence of vehicle tracks in the soil (usually during a prior training rotation period of 30 days or since the last rain or wind storm), and measures vegetation within the tracks to determine the area of plant parts being run over, the percent of the impacted parts damaged, and the percent of impacted parts expected to recover. It documents prior-damage classes based on estimated of damage that plants have apparently experienced previously (as assessed from field indicators of damage such as plant shape and height). The technique was used to evaluate different vehicle types (rubber-tire wheels vs. tracks) in six area at the NTC with different soils and training intensity levels. The technique provides tabular data that can be sorted and queried to show a variety of trends related to military vehicular impacts. The technique also appears suitable for assessing other non-military off-road traffic impacts. Findings report: (1) differences in plant sensitivity of different vehicular impacts, (2) plant cover and density by species and training area, (3) the degree to which wheels have less impact than tracks, and (4) the mean percent survival is inversely proportional to the degree of prior damage received by the vegetation (i.e., plants previously impacted have lower survival than plants not previously impacted).
Date: September 2001
Creator: Hansen, D. J. & Ostler, W. K.
Partner: UNT Libraries Government Documents Department

The relative abundance of desert tortoises on the Nevada Test Site within ecological landform units

Description: Sign-survey transects were sampled in 1996 to better determine the relative abundance of desert tortoises on the Nevada Test Site (NTS). These transects were sampled within ecological land-form units (ELUs), which are small, ecologically homogeneous units of land. Two-hundred and six ELUs were sampled by walking 332 transects totaling 889 kilometers (km). These ELUs covered 528 km{sup 2}. Two-hundred and eight-one sign were counted. An average of 0.32 sign was found per km walked. Seventy percent of the area sampled had a very low abundance of tortoises, 29% had a low abundance, and 1% had a moderate abundance. A revised map of the relative abundance of desert tortoise on the NTS is presented. Within the 1,330 km{sup 2} of desert tortoise habitat on the NTS, 49% is classified as having no tortoises or a very low abundance, 18% has a low or moderate abundance, 12% is unclassified land being used by the Yucca Mountain Site Characterization Project, and the remaining 21% still has an unknown abundance of desert tortoises. Based on the results of this work, the amount of tortoise habitat previously classified as having an unknown or low-moderate abundance, and on which clearance surveys and on-site monitoring was required, has been reduced by 20%.
Date: September 1, 1998
Creator: Woodward, R.; Rautenstrauch, K.R.; Hall, D.B. & Ostler, W.K.
Partner: UNT Libraries Government Documents Department

Reclamation of disturbed arid lands maximizing effectiveness to ensure mission sustainability

Description: Much of US Department of Defense training and testing areas is on arid and semiarid land. Testing and training activities are often more devastating to arid lands than more mesic areas, and consequently, can threaten the continuation of military testing and training operations in these areas. Under current technology, it is estimated that up to 35% of revegetation projects in arid areas will fail. Current gaps exist in distinguishing among various degrees of sustainable and nonsustainable impacts from earth-disturbing activities in desert ecosystems. Research is also needed to determine how to optimize reclamation efforts to ensure sustainability on training lands. This project included the establishment of reclamation study plots representing three levels of disturbance ranging from moderate to very heavily disturbed sites. Several new and cost-effective techniques for revegetation of disturbed training lands are being examined at Fort Irwin--the National Training Center in the Mojave Desert of California. Major treatments include novel irrigation designs, amendments to enhance soil microbes and nutrient cycling, soil stabilization, decompaction of soils, and use of adapted species. These treatments at Fort Irwin are being examined at 13 locations that have different soil conditions. Results of the first year of these trails will be presented.
Date: February 1, 2000
Creator: Ostler, W. K.; Anderson, D. & Sparks, R.
Partner: UNT Libraries Government Documents Department

Secondary plant succession on disturbed sites at Yucca Mountain, Nevada

Description: This report presents the results of a study of secondary plant succession on disturbed sites created during initial site investigations in the late 1970s and early 1980s at Yucca Mountain, NV. Specific study objectives were to determine the rate and success of secondary plant succession, identify plant species found in disturbances that may be suitable for site-specific reclamation, and to identify environmental variables that influence succession on disturbed sites. During 1991 and 1992, fifty seven disturbed sites were located. Vegetation parameters, disturbance characteristics and environmental variables were measured at each site. Disturbed site vegetation parameters were compared to that of undisturbed sites to determine the status of disturbed site plant succession. Vegetation on disturbed sites, after an average of ten years, was different from undisturbed areas. Ambrosia dumosa, Chrysothamnus teretifolius, Hymenoclea salsola, Gutierrezia sarothrae, Atriplex confertifolia, Atriplex canescens, and Stephanomeria pauciflora were the most dominant species across all disturbed sites. With the exception of A. dumosa, these species were generally minor components of the undisturbed vegetation. Elevation, soil compaction, soil potassium, and amounts of sand and gravel in the soil were found to be significant environmental variables influencing the species composition and abundance of perennial plants on disturbed sites. The recovery rate for disturbed site secondary succession was estimated. Using a linear function (which would represent optimal conditions), the recovery rate for perennial plant cover, regardless of which species comprised the cover, was estimated to be 20 years. However, when a logarithmic function (which would represent probable conditions) was used, the recovery rate was estimated to be 845 years. Recommendations for future studies and site-specific reclamation of disturbances are presented.
Date: December 1, 1994
Creator: Angerer, J.P.; Ostler, W.K.; Gabbert, W.D. & Schultz, B.W.
Partner: UNT Libraries Government Documents Department

Plant succession on disturbed sites in four plant associations in the Northern Mojave Desert

Description: The US Department of Energy (DOE) is characterizing Yucca Mountain Nevada, as a potential site for long-term underground storage of high-level nuclear waste. DOE is committed to reclaim all lands disturbed by the project, and return them to a stable ecological state, with a composition and productivity similar to predisturbance conditions. A study was implemented to assess plant species which naturally invade disturbed sites in the Yucca Mountain Project Area. In 1991 and 1992 study plots were established on disturbed sites. Sites were characterized by disturbance type (i.e., road, drill pad, etc.), disturbance severity, vegetation association, time since abandonment, and topographic placement. Density of all perennial plant species was measured on disturbed and undisturbed plots. The species with the highest density in disturbed sites was Chrysothamnus teretifolia. This species was not a major contributor in undisturbed sites. In the undisturbed sites Ambrosia dumosa had the highest density of perennial plant species but was also high in density in the disturbance sites. Total species density was higher in undisturbed sites compared to disturbed sites. Plant species density analysis compared disturbed and undisturbed vegetation associations. Results will be used to design reclamation field trails and to finalize the Yucca Mountain Project Reclamation Implementation Plan.
Date: December 31, 1993
Creator: Gabbert, W.D.; Schultz, B.W.; Angerer, J.P. & Ostler, W.K.
Partner: UNT Libraries Government Documents Department

The influence of annual species composition and density on perennial seedling density in four plant communities in the Northern Mojave Desert

Description: According to the Nuclear Waste Policy Act of 1982 (as amended in 1987), the US Department of Energy (DOE) must study and characterize Yucca Mountain as a potential site for long-term underground storage of high-level nuclear waste. Part of the overall site characterization program is to monitor potential impacts on the biological resources at Yucca Mountain. A part of the biological monitoring program, assessed vegetation parameters included density of annual and perennial seedlings. This data was used to evaluate: (1) seed germination and seed survival; and (2) if annual plant species density and cover influence perennial seedling survival. Twelve permanent 200 {times} 200-m ,study plots were established in each of four vegetation associations present in the Yucca Mountain Project area. During the spring of 1992, 20 to 60, 1-m{sup 2} randomly-located quadrats per study plot were measured for perennial seedling density, annual species density, and annual species composition. Perennial seedlings found in 1992 were relocated in the spring of 1993, and survival determined. Cover was measure in the spring of 1992. Annual plant density and cover was greatest in the Larrea-Lycium-Grayia vegetation association, and lowest in the Larrea-Ambrosia vegetation association. Annual seedling density had a negative exponential relationship with perennial seedling density in 1992. However, non-linear regression analysis indicated that 1992 annual seedling density had a greater impact on survival of pernnial seedlings from 1992 to 1993.
Date: December 31, 1993
Creator: Hall, P.F.; Angerer, J.P.; Ostler, W.K. & Schultz, B.W.
Partner: UNT Libraries Government Documents Department

The terrestrial ecosystem program for the Yucca Mountain Project

Description: DOE has implemented a program to monitor and mitigate impacts associated with site Characterization Activities at Yucca Mountain on the environment. This program has a sound experimental and statistical base. Monitoring data has been collected for parts of the program since 1989. There have been numerous changes in the Terrestrial Ecosystems Program since 1989 that reflect changes in the design and locations of Site Characterization Activities. There have also been changes made in the mitigation techniques implemented to protect important environmental resources based on results from the research efforts at Yucca Mountain. These changes have strengthened DOE efforts to ensure protection of the environmental during Site Characterization. DOE,has developed and implemented an integrated environmental program that protects the biotic environment and will restore environmental quality at Yucca Mountain.
Date: June 1, 1994
Creator: Ostler, W.K. & O`Farrell, T.P.
Partner: UNT Libraries Government Documents Department

Pre-treating Seed to Enhance Germination of Desert Shrubs

Description: Creosotebush [Larrea tridentata (D.C.) Cav.] and white bursage [Ambrosia dumosa (A. Gray) W.W. Payne] seeds were subjected to pre-treatments of rinsing and soaking in water and thiourea to enhance germination in laboratory experiments. The effects of darkness, temperature, seed source, and soil moisture were also evaluated in the laboratory. The best pre-treatment from the laboratory experiments, rinsing with water for 36 hours followed by drying, was field-tested at Fort Irwin, California. Two sites and two seeding dates (early March and mid April) were determined for each site. Five mulch treatments (no mulch, straw, gravel, chemical stabilizer, and plastic) were evaluated in combination with the seed pre-treatments. Field emergence was greatly enhanced with the seed pre-treatment for white bursage during the March (18-42% increase in germination) and April seedings (16-23% increase in germination). Creosotebush showed poor germination during March (2-5%) when soil temperatures averaged 15 C, but germination increased during the April trials (6-43%) when soil temperatures averaged 23 C. The seed pre-treatment during the April trials increased germination from 16-23%. The plastic mulch treatment increased germination dramatically during both the March and April trials. The plastic mulch increased soil temperatures (8-10 C)and maintained high humidity during germination. Both the chemical stabilizer and the gravel mulches improved germination over the control while the straw mulch decreased germination. These results suggest that seed pre-treatments combined with irrigation and mulch are effective techniques to establish these two dominant Mojave Desert species from seed.
Date: June 1, 2002
Creator: Ostler, W. K.; Anderson, D. C. & Hansen, D. J.
Partner: UNT Libraries Government Documents Department

Ecological Monitoring and Compliance Program 2010 Report

Description: The Ecological Monitoring and Compliance (EMAC) Program, funded through the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office (NNSA/NSO), monitors the ecosystem of the Nevada National Security Site (NNSS) and ensures compliance with laws and regulations pertaining to NNSS biota. This report summarizes the program’s activities conducted by National Security Technologies, LLC (NSTec), during calendar year 2010. Program activities included (a) biological surveys at proposed construction sites, (b) desert tortoise compliance, (c) ecosystem monitoring, (d) sensitive plant species monitoring, (e) sensitive and protected/regulated animal monitoring, (f) habitat restoration monitoring, and (g) monitoring of the Nonproliferation Test and Evaluation Complex (NPTEC). During 2010, all applicable laws, regulations, and permit requirements were met, enabling EMAC to achieve its intended goals and objectives.
Date: July 1, 2011
Creator: Hansen, D.J.; Anderson, D.C.; Hall, D.B.; Greger, P.D. & Ostler, W.K.
Partner: UNT Libraries Government Documents Department

Ecological Monitoring and Compliance Program 2011 Report

Description: The Ecological Monitoring and Compliance (EMAC) Program, funded through the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office, monitors the ecosystem of the Nevada National Security Site and ensures compliance with laws and regulations pertaining to NNSS biota. This report summarizes the program's activities conducted by National Security Technologies, LLC, during calendar year 2011. Program activities included (a) biological surveys at proposed construction sites, (b) desert tortoise compliance, (c) ecosystem monitoring, (d) sensitive plant species monitoring, (e) sensitive and protected/regulated animal monitoring, (f) habitat restoration monitoring, and (g) monitoring of the Nonproliferation Test and Evaluation Complex. During 2011, all applicable laws, regulations, and permit requirements were met, enabling EMAC to achieve its intended goals and objectives.
Date: June 13, 2012
Creator: Hansen, D. J., Anderson, D. C., Hall, D. B., Greger, P. D., Ostler, W. K.
Partner: UNT Libraries Government Documents Department