Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “ECOLOGY”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS1996

Paleobiology, community ecology, and scales of ecological pattern

The fossil record provides a wealth of data on the role of regional processes and historical events in shaping biological communities over a variety of time scales. The Quaternary record with its evidence of repeated climatic change shows that both terrestrial and marine species shifted independently rather than as cohesive assemblages over scales of thousands of years. Larger scale patterns also show a strong individualistic component to taxon dynamics; assemblage stability, when it occurs, is difficult to separate from shared responses to low rates of environmental change. Nevertheless, the fossil record does suggest that some biotic interactions influence large-scale ecological and evolutionary patterns, albeit in more diffuse and protracted fashions than those generally studied by community ecologists. These include: (1) the resistance by incumbents to the establishment of new or invading taxa, with episodes of explosive diversification often appearing contingent on the removal of incumbents at extinction events; (2) steady states of within-habitat and global diversity at longer time scales (10(7)-l0(8) yr), despite enormous turnover of taxa; and (3) morphological and biogeographic responses to increased intensities of predation and substratum disturbance over similarly long time scales. The behavior of species and communities over the array of temporal and spatial scales in the fossil record takes on additional significance for framing conservation strategies, and for understanding recovery of species, lineages, and communities from environmental changes.

NASA Discipline Exobiology↗
NASA NTRS1993

Planetary Biology and Microbial Ecology: Molecular Ecology and the Global Nitrogen cycle

This report summarizes the results of the Planetary Biology and Molecular Ecology's summer 1991 program, which was held at the Marine Biological Laboratory in Woods Hole, Massachusetts. The purpose of the interdisciplinary PBME program is to integrate, via lectures and laboratory work, the contributions of university and NASA scientists and student interns. The goals of the 1991 program were to examine several aspects of the biogeochemistry of the nitrogen cycle and to teach the application of modern methods of molecular genetics to field studies of organisms. Descriptions of the laboratory projects and protocols and abstracts and references of the lectures are presented.

Nealson, Molly Stone↗
NASA NTRS2023

Capitol Reef Ecological Conservation: Mapping Vegetation Functional Groups to Inform Invasive Vegetation Management, Ecological Conservation and Restoration in Capitol Reef National Park

Invasive exotic plant (IEP) species have been found within the park boundaries of Capitol Reef National Park (CARE) in Utah. Currently, remotely sensed datasets such as the Rangeland Analysis Platform (RAP) from the United States Department of Agriculture (USDA) have been used to investigate IEP species within the park, but validation of the national RAP program is necessary for informing decisions at a local scale. CARE seeks a remote monitoring solution that can precisely target managerial efforts within the park’s challenging terrain and hard-to-reach locations. To fulfill this objective, we harnessed Landsat 8 Operational Land Imager (OLI) imagery and leveraged Random Forest (RF) modeling to generate classification maps characterizing vegetation functional groups for 2013 and 2022 within the park. Subsequently, the Land Change Modeler (LCM) in Idrisi TerrSet facilitated the production of a predicted classification map for 2033. The team also devised an annual grass probability map to accentuate areas impacted by exotic grasses. A comparative assessment between the RF classification map and the RAP map for 2022 revealed an overall agreement of 47.41%, with disparities primarily arising from differences in bare soil and shrub areas. Significantly, the 2022 RF-generated classification map showcased an impressive overall accuracy of 92.17%. In short, the probability map, the land cover change detection spanning 2013 to 2022, and the forecasting of observed trends into the future aids in the evaluation of invasive plant impacts and facilitation of CARE’s preparedness for potential ecological disturbances. Notably, in comparison to the RAP, the RF classification method generates functional group maps that are more representative of the study area.

Vanchy Li↗
DOE OSTI2016

Application of Field Evaluations of Ecological Resources at Hanford and Other DOE Sites for Consistency of Resource Protection and Sustainability - 16404

Remediation and management of contaminated facilities, soil, sediment and biota is an essential element of the DOE-EM mission for site completion, contaminant footprint reduction, and protection of human health and the environment. Protecting ecological resources is an integral part of protecting human health because people are part of the ecosystem and rely on ecological resources for food, fiber, clean air and water, recreational, aesthetic, and cultural values. Evaluation and management require understanding the past and current conditions, as well as protecting, preserving, and enhancing ecological resources. Understanding past and current resources includes evaluation of individual and population health within a local and regional context. The objective of this research is to describe a field method of evaluating ecological resources, based on work at the Hanford Site, which can be applied to sustainability of ecological resources as another mandate of DOE. This requires objective methods to characterize and evaluate resources spatially, within a context of local and regional importance. The DOE complex is large, diverse, and multi-state. The habitats and ecological resources are diverse, and the relative importance of ecological resources to the local ecosystem, region, and human communities varies. Large and diverse sites such as Hanford, Idaho National Laboratory, Los Alamos, hold resources of substantial importance to local and regional ecosystems, as well as to the ecology and cultural values of Tribes and other residents. However, other smaller sites (e.g. Oak Ridge, Brookhaven) also hold key ecological resources to local and regional ecosystems, cultures, and economics. Understanding the relative importance of ecological resources on each remediation site at different spatial scales, within and among DOE-EM sites is critical to management, stewardship, and ensuring sustainability for generations to come. Without a standardized methodology it is difficult to develop sound remediation and management plans to protect human health and the environment. The Ecological Evaluation of Resources described in this paper is part of the Consortium for Risk Evaluation with Stakeholder Participation's (CRESP) Risk Review Project on the Hanford Site. It is an independent assessment based of on-site field evaluations that encompasses evaluations of site resources in comparison to the Columbia Basin Ecosystem prior evaluations made by DOE, the States of Washington and Oregon, Nature Conservancy and Tribes. The on-site field evaluations are the focus of the current paper. The on-site field evaluation methodology was developed to update existing information on habitat values in light of changing landscape features (edge, patch size and shape, connectivity) and the current presence of invasive species. Both aspects change with time, especially given that remediation of remediation units changes the landscape. That is, every time there is a remediation and restoration of an operable unit (remediation site) on a DOE site, it changes the adjacent landscape (and ecological resources). The changes are greater where new roads were built to access a remediation site, staging areas constructed, and as a function of the size and time-frame for the remediation. Since ecological resources form a continuum across the landscape, and activities from remediation on a given site can affect those on adjacent areas, we evaluated resources both on the remediation site itself, and on a buffer equal to the largest diameter of the remediation site. The field evaluation methodology developed at Hanford Site makes use of existing resource level maps (DOE/RL-96-32 2013) and field surveys and measurements of current vegetation and habitat conditions to evaluate potential ecological impacts associated with cleanup activities at the evaluation unit. Additional information used in the ecological resource evaluations include current Endangered and Threatened Species distribution data (both state and federal), aerial imagery, locations of waste sites and infrastructure, and species and habitats of special concern. We suggest that the field methodology developed for the Hanford Site could be used across the DOE complex to evaluate ecological resources. This would provide DOE-EM with a common data base to make long-term decisions about the protection and sustainability of resources on the DOE complex, and would provide Tribes and the public with information on ecological resources on DOE sites. Such information could be provided in a web-based format which DOE, regulators, Tribes, and the public could easily access. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2016

The ecological impact assessment of a proposed road development (the Slovak approach)

The construction of roads is one of the most widespread forms of natural landscape modification. Over the last 20 years, dozens of road constructions have been assessed in Slovakia, which makes it possible to talk about methodological positives and negatives. A special feature of Slovakia is that many planned or renovated roads are located in protected areas or are in contact with them (including Natura 2000 sites). Therefore, it is important to understand the scope of the roads' ecological impacts and find ways for their appropriate evaluation and incorporation into the Environmental Impact Assessment process. For this reason, the Ecological Impact Assessment methodology can be used as a basis for our research, which consists of three stages. In the first stage (scoping), a buffer circumventing the proposed road is created to determine the area for impact prediction and evaluation. Subsequently, the landscape structure and baseline landscape conditions are discussed, a map of current landscape structure is created and the current ecological status of the affected area is calculated. In the second stage (the evaluation of ecological resources), important ecological parts of the landscape are delineated. This step is based on the importance of previous information and its vulnerability, and leads to the mapping of the road ecological impact zone. In the third stage (impact assessment), important ecological parts are spatially correlated with the proposed road construction. Finally, the significance of ecological impacts of the activity is evaluated by applying specific criteria (duration, reversibility, magnitude, size and road ecological impact zone significance). A scale is proposed for each criterion to evaluate the total significance of impacts. In this way, detailed significant ecological impacts can be found which will help lead to proposed correct mitigation measures and a post-project analysis. - Highlights: • This paper proposes a methodology for the EcIA of road construction. • It tries to understand the spatial structure and configuration of landscape elements. • The most important ecological parts within the territory are identified. • The total significance of ecological receptors is evaluated by applying criteria.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2020

Risk to ecological resources following remediation can be due mainly to increased resource value of successful restoration: A case study from the Department of Energy's Hanford Site

Several nations are faced with the need to remediate large contaminated sites following World War II, the Cold War, and abandoned industrial sites, and to return them to productive land uses. In the United States, the Department of Energy (DOE) has the largest cleanup challenge, and its Hanford Site in the state of Washington has the most extensive and most expensive cleanup task. Ideally, the risk to ecological resources on remediation sites is evaluated before, during, and after remediation, and the risk from, or damage to, ecological resources from contaminants should be lower following remediation. In this paper, we report the risk to ecological resources before, during, and as a consequence of remediation on contaminated units requiring cleanup, and then examine the causes for changes in risk by evaluating 56 cleanup evaluation units (EUs) at the Hanford Site. In this case, remediation includes a restoration phase. In general, the risk to ecological and eco-cultural resources is currently not discernible or low at most contaminated units, increases during remediation, and decreases thereafter. Remediation often causes physical disruption to ecosystems as it reduces the risk from exposure to contaminants. Most new remediation projects at the Hanford Site include ecological restoration. Ecological restoration results in the potential for the presence of higher quality resources after remediation than currently exists on these contaminated lands and facilities. Although counter-intuitive, our evaluation of the risk to ecological resources following remediation indicated that a significant percentage of units (61%) will be at increased risk in the post-remediation period. This increased risk is due to DOE's successful remediation and restoration that results in a higher percent of native vegetation and higher ecological value on the sites in the post-remediation period than before. These newly-created resources can then be at risk from post-remediation activities. Risks to these new higher quality resources include the potential for spread of invasive species and of noxious grasses used in previous cleanup actions, disruption of ecosystems (including those with state or federally listed species and unique ecosystems), compaction of soil, use of pesticides to control invasive species, and the eventual need for continued monitoring activities. Thus, by greatly improving the existing habitat and health of eco-receptors, and maintaining habitat corridors between high quality habitats, the ecological resources in the post-remediated units are at risk unless care is taken to protect them. Many of the negative effects of both remediation and future monitoring (or other future land uses) can be avoided by planning and management early in the remediation process. We suggest DOE and other agencies convene a panel of managers, remediation scientists, regulators, environmental and ecological scientists, Native Americans, economists, and the public to develop a generic list of performance metrics for the restoration phase of remediation, including evaluation of success, which could be applied across the DOE complex.

54 ENVIRONMENTAL SCIENCES↗