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Arbuscular Mycorrhizal Colonization of Larrea Tridentata and Ambrosia Dumosa Roots Varies With Precipitation and Season in the Mojave Desert

Description: The percentage of fine roots colonized by arbuscular mycorrhizal (AM) fungi varied with season and with species in the co-dominant shrubs Lurreu tridentutu and Ambrosia dumosu at a site adjacent to the Nevada Desert FACE (Free-Air CO{sub 2} Enrichment) Facility (NDFF) in the Mojave Desert. We excavated downward and outward from the shrub bases in both species to collect and examine fine roots (< 1.0 mm diameter) at monthly intervals throughout 2001 and from October 2002 to September 2003. Fu… more
Date: January 1, 2004
Creator: Apple, M. E.; Thee, C. I.; Smith-Longozo, V. L.; Cogar, C. R.; Wells, C. E. & Nowak, R. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

CO2 Effects on Mojave Desert Plant Interactions

Description: Seasonal and interannual droughts characteristic of deserts have the potential to modify plant interactions as atmospheric CO{sub 2} concentrations continue to rise. At the Nevada Desert FACE (free-air CO{sub 2} enrichment) facility in the northern Mojave Desert, the effects of elevated atmospheric C02 (550 vs. ambient {approx}360 {micro}mol mol{sup -1}) on plant interactions were examined during two years of high and low rainfall. Results suggest that CO{sub 2} effects on the interaction betwe… more
Date: January 1, 2004
Creator: Defalco, L. A.; Fernandez, G. C.; Smith, S. D. & Nowak, R. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Survival Estimates for the Passage of Spring-Migrating Juvenile Salmonids through Snake and Columbia River Dams and Reservoirs, 2003-2004 Annual Report.

Description: For juvenile chinook salmon Oncorhynchus tshawytscha, sockeye salmon O. nerka, and steelhead O. mykiss that migrate through reservoirs, hydroelectric projects, and free-flowing sections of the Snake and Columbia Rivers, survival estimates are essential to develop effective strategies for recovering depressed stocks. Many management strategies were based on estimates of system survival (Raymond 1979; Sims and Ossiander 1981) derived in a river system considerably different from today's (Williams… more
Date: January 2004
Creator: Smith, Steven G.; Muir, William D. & Zabel, Richard W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

How plant functional-type, weather, seasonal drought and soil physical properties alter water and energy fluxes of an oak-grass savanna and an annual grassland.

Description: Savannas and open grasslands often co-exist in semi-arid regions. Questions that remain unanswered and are of interest to biometeorologists include: how do these contrasting landscapes affect the exchanges of energy on seasonal and annual time scales; and, do biophysical constraints imposed by water supply and water demand affect whether the land is occupied by open grasslands or savanna? To address these questions, and others, we examine how a number of abiotic, biotic and edaphic factors modu… more
Date: May 1, 2004
Creator: Baldocchi, DD, Xu L, Kiang N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Comment on ''Sensitivity Analysis and Determination of Streambed Leakance and Aquifer Hydraulic Properties'' by Xunhong Chen and Xi Chen, Journal of Hydrology, 2003, v.284, 270-284

Description: Recently, studies of the Platte River watershed have gained significant attention from federal and Nebraska, USA, state agencies due to the importance of groundwater/surface-water interactions under drought conditions. Using archive data from a 1983 pumping test, Chen and Chen (2003) interpret the hydraulic properties of the alluvium and a streambed of the Platte River near Kearney, Nebraska, and compare their data with results of other studies performed over the past several years. Three impor… more
Date: May 17, 2004
Creator: Kollet, S
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Use of Produced Water in Recirculating Cooling Systems at Power Generating Facilities

Description: The purpose of this study is to evaluate produced water as a supplemental source of water for the San Juan Generating Station (SJGS). This study incorporates elements that identify produced water volume and quality, infrastructure to deliver it to SJGS, treatment requirements to use it at the plant, delivery and treatment economics, etc. SJGS, which is operated by Public Service of New Mexico (PNM) is located about 15 miles northwest of Farmington, New Mexico. It has four units with a total gen… more
Date: August 1, 2004
Creator: DiFilippo, Michael N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

USE OF PRODUCED WATER IN RECIRCULATING COOLING SYSTEMS AT POWER GENERATING FACILITIES

Description: The purpose of this study is to evaluate produced water as a supplemental source of water for the San Juan Generating Station (SJGS). This study incorporates elements that identify produced water volume and quality, infrastructure to deliver it to SJGS, treatment requirements to use it at the plant, delivery and treatment economics, etc. SJGS, which is operated by Public Service of New Mexico (PNM) is located about 15 miles northwest of Farmington, New Mexico. It has four units with a total gen… more
Date: August 1, 2004
Creator: DiFilippo, Michael N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Vegetation study in support of the design and optimization of vegetative soil covers, Sandia National Laboratories, Albuquerque, New Mexico.

Description: A vegetation study was conducted in Technical Area 3 at Sandia National Laboratories, Albuquerque, New Mexico in 2003 to assist in the design and optimization of vegetative soil covers for hazardous, radioactive, and mixed waste landfills at Sandia National Laboratories/New Mexico and Kirtland Air Force Base. The objective of the study was to obtain site-specific, vegetative input parameters for the one-dimensional code UNSAT-H and to identify suitable, diverse native plant species for use on v… more
Date: November 1, 2004
Creator: Peace, Gerald (Jerry) L.; Goering, Timothy James (GRAM inc., Albuquerque, NM); Knight, Paul J. (Marron and Associates, Albuquerque, NM) & Ashton, Thomas S. (Marron and Associates, Albuquerque, NM)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Use of an Eye-Safe, Portable LIDAR for Remote Wildland Fire and Smoke Detection

Description: During periods of drought when surface water supplies are severely limited, wildland forest fires tend to become more frequent and often can grow into major fires that threaten valuable timber, real estate, and even human lives. Fire-fighting crews are critically dependent upon accurate and timely weather data to help ensure that individuals are not inadvertently exposed to dangerous conditions and to enhance normal fire-fighting activities. To that end, the use of an eye-safe, portable lidar f… more
Date: November 29, 2004
Creator: MATTHEW, PARKER
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

ARM Climate Research Facility Annual Report 2004

Description: Like a rock that slowly wears away beneath the pressure of a waterfall, planet earth?s climate is almost imperceptibly changing. Glaciers are getting smaller, droughts are lasting longer, and extreme weather events like fires, floods, and tornadoes are occurring with greater frequency. Why? Part of the answer is clouds and the amount of solar radiation they reflect or absorb. These two factors clouds and radiative transfer represent the greatest source of error and uncertainty in the current ge… more
Date: December 31, 2004
Creator: Voyles, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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