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USDA Forest Service - General Technical Report RMRS-GTR | 2006

Forest Inventory and Analysis National Data Quality Assessment Report for 2000 to 2003

James Pollard; James A. Westfall; Paul Patterson; David L. Gartner; Mark H. Hansen; Olaf Kuegler

The Forest Inventory and Analysis program (FIA) is the key USDA Forest Service (USFS) program that provides the information needed to assess the status and trends in the environmental quality of the Nations forests. The goal of the FIA Quality Assurance (QA) program is to provide a framework to assure the production of complete, accurate and unbiased forest information of known quality. Specific Measurement Quality Objectives (MQO) for precision are designed to provide a window of performance that we are striving to achieve for every field measurement. These data quality goals were developed from knowledge of measurement processes in forestry and forest ecology, as well as the program needs of FIA. This report is a national summary and compilation of MQO analyses by regional personnel and the National QA Advisor.The efficacy of the MQO, as well as the measurement uncertainty associated with a given field measurement, can be tested by comparing data from blind check plots where, in addition to the field measurements of the standard FIA crew, a second QA measurement of the plot was taken by a crew without knowledge of the first crews results. These QA data were collected between 2000 and 2003 and analyzed for measurement precision between FIA crews.The charge of this task team was to use the blind-check data to assess the FIA programs ability to meet data quality goals as stated by the MQO. The results presented indicate that the repeatability was within project goals for a wide range of measurements across a variety of forest and nonforest environments. However, there were some variables that displayed noncompliance with MQO goals. In general, there were two types of noncompliance: the first is where all the regions were below the MQO standard, and the second is where a subset of the regions was below the MQO standards or was substantially different from the other remaining regions. Results for each regional analysis are presented in appendix tables. In the course of the study, the task team discovered that there were difficulties in analyzing seedling species and seedling count variables for MQO compliance, and recommends further study of the issue. Also the task team addresses the issue of trees missed or added and recommends additional study of this issue. Lastly, the team points out that traditional MQO analysis of the disturbance and treatment variables may not be adequate.Some attributes where regional compliance rates are dissimilar suggest that regional characteristics (environmental variables such as forest type, physiographic class, and forest fragmentation) may have an impact on the ability to obtain consistent measurements. Additionally, differences in data collection protocols may cause differences in compliance rates. For example, a particular variable may be measured with a calibrated instrument in one region, while ocularly estimated in another region.


Journal of Freshwater Ecology | 1981

Investigator Differences Associated with a Kicking Method for Sampling Macroinvertebrates

James Pollard

ABSTRACT A Standardized Traveling Kicking Method (STKM) was tested for sensitivity to sampling personnel in collecting stream macroinvertebrates. Collections taken by different persons showed significant differences in relative standing crop in depauperate stream reaches, and minor differences for percent community composition in fauna rich reaches. The STKM appears to be an excellent, tool for monitoring community composition changes in riffle habitats, but requires further development for faunal-poor reaches of stream benthos.


Toxicology and Applied Pharmacology | 2016

Immunotoxicological and neurotoxicological profile of health effects following subacute exposure to geogenic dust from sand dunes at the Nellis Dunes Recreation Area, Las Vegas, NV

Deborah E. Keil; Brenda J. Buck; Dirk Goossens; Mallory Leetham; Lacey Murphy; James Pollard; Margaret J. Eggers; Brett T. McLaurin; Russell Gerads; Jamie C. DeWitt

Exposure to geogenic particulate matter (PM) comprised of mineral particles has been linked to human health effects. However, very little data exist on health effects associated with geogenic dust exposure in natural settings. Therefore, we characterized particulate matter size, metal chemistry, and health effects of dust collected from the Nellis Dunes Recreation Area (NDRA), a popular off-road vehicle area located near Las Vegas, NV. Adult female B6C3F1 mice were exposed to several concentrations of mineral dust collected from active and vegetated sand dunes in NDRA. Dust samples (median diameter: 4.4 μm) were suspended in phosphate-buffered saline and delivered at concentrations ranging from 0.01 to 100 mg dust/kg body weight by oropharyngeal aspiration. ICP-MS analyses of total dissolution of the dust resulted in aluminum (55,090 μg/g), vanadium (70 μg/g), chromium (33 μg/g), manganese (511 μg/g), iron (21,600 μg/g), cobalt (9.4 μg/g), copper (69 μg/g), zinc (79 μg/g), arsenic (62 μg/g), strontium (620 μg/g), cesium (13 μg/g), lead 25 μg/g) and uranium (4.7 μg/g). Arsenic was present only as As(V). Mice received four exposures, once/week over 28-days to mimic a month of weekend exposures. Descriptive and functional assays to assess immunotoxicity and neurotoxicity were performed 24 h after the final exposure. The primary observation was that 0.1 to 100 mg/kg of this sand dune derived dust dose-responsively reduced antigen-specific IgM antibody responses, suggesting that dust from this area of NDRA may present a potential health risk.


Toxicology and Applied Pharmacology | 2016

Health effects following subacute exposure to geogenic dusts from arsenic-rich sediment at the Nellis Dunes Recreation Area, Las Vegas, NV

Jamie C. DeWitt; Brenda J. Buck; Dirk Goossens; Qing Hu; Rebecca Chow; Winnie David; Sharon M. Young; Mallory Leetham-Spencer; Lacey Murphy; James Pollard; Brett T. McLaurin; Russell Gerads; Deborah E. Keil

Geogenic dust from arid environments is a possible inhalation hazard for humans, especially when using off-road vehicles that generate significant dust. This study focused on immunotoxicological and neurotoxicological effects following subacute exposure to geogenic dust generated from sediments in the Nellis Dunes Recreation Area near Las Vegas, Nevada that are particularly high in arsenic; the naturally-occurring arsenic concentrations in these surficial sediments ranged from 4.8 to 346μg/g. Dust samples from sediments used in this study had a median diameter of 4.5μm and also were a complex mixture of naturally-occurring metals, including aluminum, vanadium, chromium, manganese, iron, cobalt, copper, zinc, strontium, cesium, lead, uranium, and arsenic. Adult female B6C3F1 mice exposed via oropharyngeal aspiration to 0.01 to 100mg dust/kg body weight, four times, a week apart, for 28days, were evaluated 24h after the last exposure. Peripheral eosinophils were increased at all concentrations, serum creatinine was dose responsively increased beginning at 1.0mg/kg/day, and blood urea nitrogen was decreased at 10 and 100mg/kg/day. Antigen-specific IgM responses and natural killer cell activity were dose-responsively suppressed at 0.1mg/kg/day and above. Splenic CD4+CD25+ T cells were decreased at 0.01, 0.1, 10, and 100mg/kg/day. Antibodies against MBP, NF-68, and GFAP were selectively reduced. A no observed adverse effect level of 0.01mg/kg/day and a lowest observed adverse effect level of 0.1mg/kg/day were determined from IgM responses and natural killer cell activity, indicating that exposure to this dust, under conditions similar to our design, could affect these responses.


Toxicology reports | 2017

Health effects following subacute exposure to geogenic dust collected from active drainage surfaces (Nellis Dunes Recreation Area, Las Vegas, NV)

Jamie C. DeWitt; Brenda J. Buck; Dirk Goossens; James Pollard; Brett T. McLaurin; Russell Gerads; Deborah E. Keil

Graphical abstract


Journal of Freshwater Ecology | 1984

Field Washing Efficiency in Removal of Macroinvertebrates from Aquatic Vegetation Mats

James Pollard; Susan M. Melancon

ABSTRACT A new field washing technique for removal of invertebrates from aquatic vegetation was investigated. This technique, which involved field washing samples in alchohol (ETOH), was developed and tested with aquatic vegetation samples from two undisturbed lotic systems in Southern Nevada. Results indicated that approximately 60% of the animals were removed from watercress and algal mat samples by vigorous water washing in a bucket. Field washing of algal and watercress samples using ETOH removed an additional 20–40% of the total macroinvertebrates, with ETOH wash efficiency being higher in the watercress samples. Generally, tightly clinging organisms such as hydroptilid caddisfly pupae or case building midges were the only invertebrates not effectively removed from aquatic vegetation samples by a cambination of alchohol and water-washing in the field.


Toxicology reports | 2018

Nevada Desert Dust With Heavy Metals Suppresses Igm Antibody Production

Deborah E. Keil; Brenda J. Buck; Dirk Goossens; Brett T. McLaurin; Lacey Murphy; Mallory Leetham-Spencer; James Pollard; Russell Gerads; Jamie C. DeWitt

Graphical abstract


Environmental Toxicology and Chemistry | 1986

Evaluation of Sesoil, Przm and Pestan in a laboratory column leaching experiment

Susan M. Melancon; James Pollard; Stephen C. Hern


Environmental Monitoring and Assessment | 2007

Selenium concentrations in water and plant tissues of a newly formed arid wetland in Las Vegas, Nevada.

James Pollard; James V. Cizdziel; Krystyna Anne Stave; Michelle Reid


Environmental Toxicology and Chemistry | 1985

A field test of the exams model in the Monongahela River

James Pollard; Stephen C. Hern

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Brett T. McLaurin

Bloomsburg University of Pennsylvania

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Dirk Goossens

Katholieke Universiteit Leuven

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Lacey Murphy

Montana State University

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David L. Gartner

United States Department of Agriculture

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James A. Westfall

United States Department of Agriculture

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