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Workshop on Plant Dispersal and Migration Modeling. Final Report for period June 1, 2001 - May 31, 2002

Description: Global environmental change is causing shifts in the geographical locations of habitats suitable for particular plant species. While it is established that the future distributions of plant species will be strongly influenced by the ability of plants to migrate to sites of suitable habitat, our ability to predict potential and actual migration rates is rudimentary. This workshop organized by the Global Change and Terrestrial Ecosystems (GCTE) core project of the International Geosphere-Biosphere Program provided scientists with interests and expertise in global change and plant migration with a forum for developing a new collaborative synthesis of understanding on long distance dispersal and migration modeling. This grant from the U.S. Department of Energy, Office of Biological and Environmental Research, provided partial support for the workshop by supporting the participation of U.S. scientists.
Date: November 4, 2002
Creator: Pitelka, L. F.
Partner: UNT Libraries Government Documents Department

U.S. Department of Energy (DOE)--Surface Biogeochemical Research (SBR) 6th Annual PI Meeting: Abstracts

Description: On behalf of the Subsurface Biogeochemical Research (SBR) program managers in the Climate and Environmental Sciences Division (CESD), Office of Biological and Environmental Research (BER), welcome to the 2011 SBR Principal Investigators meeting. Thank you in advance for your attendance and your presentations at this year's meeting. As the events in Japan continue to unfold, we are all reminded that the research we perform on radionuclide behavior in the environment has implications beyond legacy waste cleanup and in fact has its place in the discussion on the expanded use of nuclear power. As in the past, there are three broad objectives to the Principal Investigators meeting: (1) to provide opportunities to share research results and promote interactions among the SBR scientists and other invited guests; (2) to evaluate the progress of each project within the program; and (3) to showcase the scientific expertise and research progress over the past year to senior managers within the DOE Office of Science, the technology offices within DOE, and other invited attendees from other Federal Agencies. This past year has seen a few significant changes within BER and within the SBR program. In November, our Associate Director for BER, Anna Palmisano, retired from Federal service. Just this month, Dr. Sharlene Weatherwax (Division Director for Biological Systems Sciences) has been named as the new Associate Director for BER. In August, BER welcomed Dr. Gary Geernaert as the new Division Director for CESD. Gary joins the division from Los Alamos National Laboratory with a background in atmospheric science. Within the SBR program, a new Strategic Plan was completed last June (currently posted on the SBR and the Office of Science website). The new strategic plan is intended to foster integration within the Environmental Systems Science portion of the BER budget that includes both SBR and Terrestrial ...
Date: April 11, 2011
Creator: Hazen Ed., T.C.
Partner: UNT Libraries Government Documents Department

Developing microbe-plant interactions for applications in plant-growth promotion and disease control, production of useful compounds, remediation, and carbon sequestration

Description: Interactions between plants and microbes are an integral part of our terrestrial ecosystem. Microbe-plant interactions are being applied in many areas. In this review, we present recent reports of applications in the areas of plant-growth promotion, biocontrol, bioactive compound and biomaterial production, remediation and carbon sequestration. Challenges, limitations and future outlook for each field are discussed.
Date: March 1, 2009
Creator: Wu, C. H.; Bernard, S.; Andersen, G.L. & Chen, W.
Partner: UNT Libraries Government Documents Department

PATHWAY: a simulation model of radionuclide-transport through agricultural food chains

Description: PATHWAY simulates the transport of radionuclides from fallout through an agricultural ecosystem. The agro-ecosystem is subdivided into several land management units, each of which is used either for grazing animals, for growing hay, or for growing food crops. The model simulates the transport of radionuclides by both discrete events and continuous, time-dependent processes. The discrete events include tillage of soil, harvest and storage of crops,and deposition of fallout. The continuous processes include the transport of radionuclides due to resuspension, weathering, rain splash, percolation, leaching, adsorption and desorption of radionuclides in the soil, root uptake, foliar absorption, growth and senescence of vegetation, and the ingestion assimilation, and excretion of radionuclides by animals. Preliminary validation studies indicate that the model dynamics and simulated values of radionuclide concentrations in several agricultural products agree well with measured values when the model is driven with site specific data on deposition from world-wide fallout.
Date: January 1, 1982
Creator: Kirchner, T.B.; Whicker, F.W. & Otis, M.D.
Partner: UNT Libraries Government Documents Department

A program to assess microbial impacts on nuclear waste containment

Description: In this paper we discuss aspects of a comprehensive program to identify and bound potential effects of microorganisms on long-term nuclear waste containment, using as examples, studies conducted within the Yucca Mountain Project. A comprehensive program has been formulated which cuts across standard disciplinary lines to address the specific concerns of microbial activity in a radioactive waste repository. Collectively, this program provides bounding parameters of microbial activities that modify the ambient geochemistry and hydrology, modify corrosion rates, and transport and transform radionuclides under conditions expected to be encountered after geological waste emplacement. This program is intended to provide microbial reaction rates and bounding conditions in a form that can be integrated into existing chemical and hydrological models. The inclusion of microbial effects will allow those models to more accurately assess long term repository integrity.
Date: February 20, 1996
Creator: Horn, J. & Meike, A.
Partner: UNT Libraries Government Documents Department

Landscape characterization and biodiversity research

Description: Rapid deforestation often produces landscape-level changes in forest characteristics and structure, including area, distribution, and forest habitat types. Changes in landscape pattern through fragmentation or aggregation of natural habitats can alter patterns of abundance for single species and entire communities. Examples of single-species effects include increased predation along the forest edge, the decline in the number of species with poor dispersal mechanisms, and the spread of exotic species that have deleterious effects (e.g., gypsy moth). A decrease in the size and number of natural habitat patches increases the probability of local extirpation and loss of diversity of native species, whereas a decline in connectivity between habitat patches can negatively affect species persistence. Thus, there is empirical justification for managing entire landscapes, not just individual habitat types, in order to insure that native plant and animal diversity is maintained. A landscape is defined as an area composed of a mosaic of interacting ecosystems, or patches, with the heterogeneity among the patches significantly affecting biotic and abiotic processes in the landscape. Patches comprising a landscape are usually composed of discrete areas of relatively homogeneous environmental conditions and must be defined in terms of the organisms of interest. A large body of theoretical work in landscape ecology has provided a wealth of methods for quantifying spatial characteristics of landscapes. Recent advances in remote sensing and geographic information systems allow these methods to be applied over large areas. The objectives of this paper are to present a brief overview of common measures of landscape characteristics, to explore the new technology available for their calculation, to provide examples of their application, and to call attention to the need for collection of spatially-explicit field data.
Date: March 1, 1995
Creator: Dale, V.H.; Offerman, H.; Frohn, R. & Gardner, R.H.
Partner: UNT Libraries Government Documents Department

Vegetation management 1994 fiscal year end report

Description: This year-end report evaluates vegetation management operations on the Hanford reservation conducted during fiscal year (FY) 1994 and proposed control methods to be used in FY 1995 and following years. The 1995 control methods proposed are based on an evaluation of past and current ALARA principles, employee safety, environmental impacts, applicable regulations, site esthetics, and other site-specific factors.
Date: February 1, 1995
Creator: Rodriguez, J.M.
Partner: UNT Libraries Government Documents Department

Terrestrial habitat mapping of the Oak Ridge Reservation: 1996 Summary

Description: The US DOE is in the process of remediating historical contamination on the Oak Ridge Reservation (ORR). Two key components are ecological risk assessment and monitoring. In 1994 a strategy was developed and a specific program was initiated to implement the strategy for the terrestrial biota of the entire ORR. This document details results of the first task: development of a habitat map and habitat models for key species of interest. During the last 50 years ORR has been a relatively protected island of plant and animal habitats in a region of rapidly expanding urbanization. A preliminary biodiversity assessment of the ORR by the Nature Conservancy in 1995 noted 272 occurrences of significant plant and animal species and communities. Field surveys of threatened and endangered species show that the ORR contains 20 rare plant species, 4 of which are on the state list of endangered species. The rest are either on the state list of threatened species or listed as being of special concern. The ORR provides habitat for some 60 reptilian and amphibian species; more than 120 species of terrestrial birds; 32 species of waterfowl, wading birds, and shorebirds; and about 40 mammalian species. The ORR is both a refuge for rare species and a reservoir of recruitment for surrounding environments and wildlife management areas. Cedar barrens, river bluffs, and wetlands have been identified as the habitat for most rare vascular plant species on the ORR.
Date: September 1, 1996
Creator: Washington-Allen, R.A. & Ashwood, T.L.
Partner: UNT Libraries Government Documents Department

Managing forests as ecosystems: A success story or a challenge ahead?

Description: To manage forests as ecosystems, the many values they hold for different users must be recognized, and they must be used so that those assets are not destroyed. Important ecosystem features of forests include nutrient cycling, habitat, succession, and water quality. Over time, the ways in which humans value forests have changed as forest uses have altered and as forests have declined in size and quality. Both ecosystem science and forest ecology have developed approaches that are useful to manage forests to retain their value. A historical perspective shows how changes in ecology, legislation, and technology have resulted in modern forest-management practices. However, current forest practices are still a decade or so behind current ecosystem science. Ecologists have done a good job of transferring their theories and approaches to the forest manager classroom but have done a poor job of translating these concepts into practice. Thus, the future for ecosystem management requires a closer linkage between ecologists and other disciplines. For example, the changing ways in which humans value forests are the primary determinant of forest-management policies. Therefore, if ecologists are to understand how ecosystem science can influence these policies, they must work closely with social scientists trained to assess human values.
Date: October 1, 1997
Creator: Dale, V.H.
Partner: UNT Libraries Government Documents Department

Photosynthesis, Nitrogen, Their Adjustment and its Effects on Ecosystem Carbon Gain at Elevated CO{sub 2}l. A Comparison of Loblolly and Ponderosa Pines

Description: A functional understanding of terrestrial ecosystem carbon processes is essential for two reasons. First, carbon flow is a most fundamental aspects of ecosystem function as it mediates most of the energy flow in these systems. Second, carbon flow also mediates the majority of energy flow in the global economy and will do for the foreseeable future. The increased atmospheric carbon dioxide and its inevitable flow through global ecosystems will influence ecosystem processes. There is, of course, great interest in the potential of ecosystems to sequester some of the carbon being loaded into the atmosphere by economic activity.
Date: December 1, 1996
Creator: Ball, J. Timothy; Eichelmann, Hillar Y.; Tissue, David T.; Lewis, James D.; Picone, Johnn B. & Ross, Peter D.
Partner: UNT Libraries Government Documents Department

Carbon Sequestration in Terrestrial Ecosystems: A Status Report on R and D Progress

Description: Sequestration of carbon in terrestrial ecosystems is a low-cost option that may be available in the near-term to mitigate increasing atmospheric CO{sub 2} concentrations, while providing additional benefits. Storing carbon in terrestrial ecosystems can be achieved through maintenance of standing aboveground biomass, utilization of aboveground biomass in long-lived products, or protection of carbon (organic and inorganic) compounds present in soils. There are potential co-benefits from efforts to sequester carbon in terrestrial ecosystems. For example, long-lived valuable products (wood) are produced, erosion would be reduced, soil productivity could be improved through increased capacity to retain water and nutrients, and marginal lands could be improved and riparian ecosystems restored. Another unique feature of the terrestrial sequestration option is that it is the only option that is ''reversible'' should it become desirable or permissible. For example, forests that are created are thus investments which could be harvested should CO{sub 2} emissions be reduced in other ways to acceptable levels 50-100 years from now.
Date: August 30, 2001
Creator: Jacobs, G.K.
Partner: UNT Libraries Government Documents Department

Final Report: Fine-Mesh Treatment of the Land Component of a Global Climate Model, September 1, 1994 - August 31, 1998

Description: The characteristics of land important for climate are very heterogeneous, as are the key atmospheric inputs to land, i.e. precipitation and radiation. To adequately represent this heterogeneity, state-of-the-art climate models should represent atmospheric inputs to land, land properties, and the dynamical changes of land at the highest resolution accessible by climate models. The research funded under this project focused on the development of an alternative approach to this problem in which a sub-mesh is imposed on each atmospheric model grid square. This allows representation of the land climate dynamics at a higher resolution than that achievable in the global atmospheric models. The high spatial detail of the fine-mesh treatment provides not only a more accurate representation of land processes to the atmospheric model, but also the opportunity for direct downscaling of the surface climate. The principal objectives were: (1) To complete the development of fine-mesh data structures in the VBATS model and its link to CCM2; (2) To improve BATS model parameterizations; (3) To complete and refine fine-mesh atmospheric parameterizations; and (4) To conduct sensitivity studies. The primary shift in goals has been to include and emphasize linkages to CCM3 which has been publicly released as of May 1996.
Date: August 31, 1998
Creator: Dickinson, Robert E.
Partner: UNT Libraries Government Documents Department

Landscape ecosystems of the University of Michigan Biological Station: Ecosystem diversity and ground-cover diversity

Description: The aim of this research is to provide an understanding of the three-dimensional (air-earth-organism) units of the landscape of the University of Michigan Biological Station (UMBS) that the author calls landscape ecosystem types, or simply ecosystems. Specifically, he has focused on the kinds, spatial location and patterns, and composition (physiography, soil, vegetation) of the local landscape ecosystem types of UMBS and Colonial Point. Future research on the functioning of these ecosystems together with inventories of their plant and animal life will add significantly to the landscape ecology research that has been initiated. A major reason for this research is to provide the conceptual basis and baseline data for understanding ecosystem change. Although it is popular to speak of climate change, entire ecosystems change; some components change faster than others.
Date: December 31, 1995
Creator: Pearsall, D.R.
Partner: UNT Libraries Government Documents Department

Forest surveys and wildfire assessment in the Los Alamos Region; 1998-1999

Description: To better understand the structural characteristics of vegetation in the Los Alamos region, the authors conducted two years of field surveys and associated analyses. This report introduces field methods, lists the summarized field data, and discusses the results of preliminary spatial analyses. During 1998 and 1999, seventy-six terrestrial plant communities were sampled for topographic characteristics, soil surface features, and vegetational conditions. A nested, randomized design was used to select the plot locations and to guide the sampling of the plot. The samples included a variety of fuel types, including surface fuels and ground fuels, shrubby and small tree fuels, and overstory fuels. Species composition data were also collected. The fuels data were summarized by vegetation type and evaluated for the topographic and spatial relationships of major field categories. The results of these analyses indicate that many of the fuels categories depend on topographic factors in a linear and curvilinear fashion. In particular, middle elevations within the Los Alamos region tend to support more surface fuels and ground fuels, whereas large-diameter trees are most dense at higher elevations and are specific to community types at these elevations. Small-diameter trees occur in more dense stands at lower and middle elevations and on specific soil and topographic conditions. Areas that burned in 1954 were found to be relatively free of fuels. The implications are that the western portions of the Los Alamos region are at risk from wildfire during dry, summer periods.
Date: June 1, 2000
Creator: Balice, Randy G.; Miller, Jay D.; Oswald, Brian P.; Edminster, Carl & Yool, Stephen R.
Partner: UNT Libraries Government Documents Department

Terrestrial ecosystem responses to global change: A research strategy

Description: Uncertainty about the magnitude of global change effects on terrestrial ecosystems and consequent feedbacks to the atmosphere impedes sound policy planning at regional, national, and global scales. A strategy to reduce these uncertainties must include a substantial increase in funding for large-scale ecosystem experiments and a careful prioritization of research efforts. Prioritization criteria should be based on the magnitude of potential changes in environmental properties of concern to society, including productivity; biodiversity; the storage and cycling of carbon, water, and nutrients; and sensitivity of specific ecosystems to environmental change. A research strategy is proposed that builds on existing knowledge of ecosystem responses to global change by (1) expanding the spatial and temporal scale of experimental ecosystem manipulations to include processes known to occur at large scales and over long time periods; (2) quantifying poorly understood linkages among processes through the use of experiments that manipulate multiple interacting environmental factors over a broader range of relevant conditions than did past experiments; and (3) prioritizing ecosystems for major experimental manipulations on the basis of potential positive and negative impacts on ecosystem properties and processes of intrinsic and/or utilitarian value to humans and on feedbacks of terrestrial ecosystems to the atmosphere.
Date: September 1, 1998
Partner: UNT Libraries Government Documents Department

Support for GCTE-LUCC open Science Conference on global change. Final report for period September 15, 1997, - September 14, 1998

Description: The Global Change and Terrestrial Ecosystems (GCTE) core project of the International Geosphere-Biosphere Program (IGBP) and the Land-Use/Cover Change (LUCC) core project of IGBP and the International Human Dimensions Program (IHDP) held a major open Science Conference in Barcelona, Spain, on 14-18 March 1998. At the Conference, scientists presented the most recent research findings from these two international projects, explored emerging cross-cutting linkages between the projects, and highlighted the importance of the regional approach to global change research. This grant from the U.S. Department of Energy, Office of Biological and Environmental Research, provided support for the Conference by contributing to the production of conference literature and by supporting the participation of U.S. scientists in the Conference.
Date: February 1, 1999
Creator: Pitelka, L.F.
Partner: UNT Libraries Government Documents Department

Ground-based grasslands data to support remote sensing and ecosystem modeling of terrestrial primary production

Description: Estimating terrestrial net primary production (NPP) using remote- sensing tools and ecosystem models requires adequate ground-based measurements for calibration, parameterization, and validation. These data needs were strongly endorsed at a recent meeting of ecosystem modelers organized by the International Geosphere-Biosphere Programme`s (IGBP`s) Data and Information System (DIS) and its Global Analysis, Interpretation, and Modelling (GAIM) Task Force. To meet these needs, a multinational, multiagency project is being coordinated by the IGBP DIS to compile existing NPP data from field sites and to regionalize NPP point estimates to various-sized grid cells. Progress at Oak Ridge National Laboratory (ORNL) on compiling NPP data for grasslands as part of the IGBP DIS data initiative is described. Site data and associated documentation from diverse field studies are being acquired for selected grasslands and are being reviewed for completeness, consistency, and adequacy of documentation, including a description of sampling methods. Data are being compiled in a database with spatial, temporal, and thematic characteristics relevant to remote sensing and global modeling. NPP data are available from the ORNL Distributed Active Archive Center (DAAC) for biogeochemical dynamics. The ORNL DAAC is part of the Earth Observing System Data and Information System, of the US National Aeronautics and Space Administration.
Date: December 31, 1995
Creator: Olson, R.J.; Turner, R.S.; Scurlock, J.M.O. & Jennings, S.V.
Partner: UNT Libraries Government Documents Department

CRADA Carbon Sequestration in Soils and Commercial Products

Description: ORNL, through The Consortium for Research on Enhancing Carbon Sequestration in Terrestrial Ecosystems (CSiTE), collaborated with The Village Botanica, Inc. (VB) on a project investigating carbon sequestration in soils and commercial products from a new sustainable crop developed from perennial Hibiscus spp. Over 500 pre-treated samples were analyzed for soil carbon content. ORNL helped design a sampling scheme for soils during the planting phase of the project. Samples were collected and prepared by VB and analyzed for carbon content by ORNL. The project did not progress to a Phase II proposal because VB declined to prepare the required proposal.
Date: January 31, 2002
Creator: Jacobs, G.K.
Partner: UNT Libraries Government Documents Department

Toxicological Benchmarks for Screening Potential Contaminants of Concern for Effects on Terrestrial Plants

Description: One of the initial stages in ecological risk assessment for hazardous waste sites is screening contaminants to determine which of them are worthy of further consideration as contaminants of potential concern. This process is termed contaminant screening. It is performed by comparing measured ambient concentrations of chemicals to benchmark concentrations. Currently, no standard benchmark concentrations exist for assessing contaminants in soil with respect to their toxicity to plants. This report presents a standard method for deriving benchmarks for this purpose (phytotoxicity benchmarks), a set of data concerning effects of chemicals in soil or soil solution on plants, and a set of phytotoxicity benchmarks for 38 chemicals potentially associated with United States Department of Energy (DOE) sites. In addition, background information on the phytotoxicity and occurrence of the chemicals in soils is presented, and literature describing the experiments from which data were drawn for benchmark derivation is reviewed. Chemicals that are found in soil at concentrations exceeding both the phytotoxicity benchmark and the background concentration for the soil type should be considered contaminants of potential concern.
Date: January 1, 1993
Creator: Suter, G. W., II
Partner: UNT Libraries Government Documents Department

Continental scale estimastes of the biotic carbon flux from land cover change: 1850 to 1980

Description: This document describes a Numeric Data Package (NDP) that contains annual carbon flux estimates from land cover change for nine regions of the world (i.e., North America, Europe, the Former Soviet Union, Pacific Developed Region, China, South and Central America, North Africa-Middle East, Tropical Africa, and South and Southeast Asia). Annual rates of land cover change and vegetation-soil response curves for each region and ecosystem are included in the database. The vegetation-soil curves are used in a bookkeeping carbon model to estimate the carbon flux with the atmosphere from the clearing or degradation of vegetation, cultivation of soils, decay of dead vegetation, and the recovery of abandoned lands. The model calculates the net flux of carbon in each region based on land cover change rates and vegetation-soil response curves for the period 1850 to 1980 (a few regions have WA cover records beginning in 1700 and carbon flux estimates ending in 1990). These data were collected and modeled in an attempt to reduce the uncertainty associated with the magnitude and time course of the flux of carbon from terrestrial vegetation to the atmosphere.
Date: March 1, 1995
Creator: Daniels, R.C.; Houghton, R.A. & Hackler, J.L.
Partner: UNT Libraries Government Documents Department