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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.

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At least 181 records · Page 10
All sourcesNASA NTRSDOE OSTI
NASA NTRS1973

ERTS-1 investigation of ecological effects of strip mining in eastern Ohio

Evidence is presented of ERTS capability to detect, map and monitor the effects of strip mining. Both enlarge ERTS imagery and statistically processed outline maps and imagery of stripped earth and standing water are compared to aerial photos of a strip mine near Coshocton, Ohio. The outline maps and decision imagery are at present limited to forming a disruption map of recently mined and unreclaimed earth and the resultant standing water within the mined area. It is planned to prepare a map of the reclaimed areas (reclamation map) within the stripped area and to detect and identify ecological effects such as vegetation kills and stream sedimentation external to the stripped areas.

Chase, P. E.↗
NASA NTRS1972

A method for phenomenological analysis of ecological data.

The experimental meaning of the phenomenological differential equations for a competing population is reviewed. It is concluded that it is virtually impossible to construct the differential equations precise enough for studying stability. We consider instead a method of phenomenological analysis which can be applied to a set of population curves. We suggest an ecological index calculated from the population curves, which indicates a group property of the entire system. As a function of time, the index is presumably insensitive to Volterra type fluctuations. A marked increase of the index's value however indicates a marked change of the environmental conditions. It is not easy to deduce the group property from the population curves alone, because a change in population is in general due to the superposition of external disturbances and Volterra fluctuations.

Huang, H.-W.↗
NASA NTRS1974

An ecological study of the KSC Turning Basin and adjacent waters

The conditions existing in the waters and bottoms of the Turning Basin, the borrow pit near Pad 39A, and the Barge Canal connecting them were investigated to determine the ecological significance of the chemical, biological, and microbiological parameters. The water quality, biological, microbiological findings are discussed. It is recommended that future dredging activities be limited in depth, and that fill materials should not be removed down to the clay strata.

Nevin, T. A.↗
NASA NTRS1977

A comment on methanogenic bacteria and the primitive ecology

As the phenotype of methanogenic bacteria is suggested to have been one of the major factors creating a dynamic balance between CO2 and CH4 in the primitive atmosphere, these organisms are thought to be very ancient. Their antiquity may be further postulated by comparative characterization of their ribosomal RNA. Accepting this antiquity, it is concluded that a carbon-dioxide-methane cycle, driven by photosynthesis, was the major carbon cycle in primitive ecology, and that photosynthesis and methanogens were thus contemporaneous.

Woese, C. R.↗
NASA NTRS1977

Localization of an experimental ecological unit in the Maradi region of Nigeria

A detailed topographical and geomorphological description of a specific ecological unit in the Maradi region of the Sahel in the Niger Republic is presented. Sandy structures are classified into active dunes and covered dunes and an extensives vocabulary is developed to describe sub-categories. The descriptions are based on meteorological data (anemometric and rainfall) from local weather stations, ground observations, aerial photographs and LANDSAT pictures. The problem of dune reactivation and desertification is discussed both from the standpoint of causes and possible counter measures.

Mainguet, M.↗
NASA NTRS1978

Use of remote sensing technology provided by the NASA/WFC Chesapeake Bay Ecological Program

Use of remote sensing technology provided through the NASA/Wallops Chesapeake Bay Ecological Program was investigated by means of extensive interviews with users. Since the inception of the Program four years ago, the technology has been used in 136 different managerial projects. Sixty-five regional managerial agencies took part in projects that the authors categorized as socioeconomic, political/managerial, monetary, legal, and other. Remote sensing technology was considered successful in 88.6 percent of the completed projects and unsuccessful in 2.8 percent.

Harman, D. M.↗
NASA NTRS1979

Central atlantic regional ecological test site: A prototype regional environmental information system, volume 1

The Central Atlantic Regional Ecological Test Site (CARETS) project was a demonstration project for introducing data from Landsat and high-altitude aircraft sensors into regional land planning and management. This report summarizes the CARETS project results and describes its output of maps, reports, computer tapes, and other products. CARETS used a geographic information system model under which land use maps were prepared from sensor data, then digitized, processed, and linked to other environmental and social data sets, and to environmental consequences such as air pollution, stream runoff, local climatic factors, and coastal erosion. Landsat data showed the test region in 1972 to be nine percent urban and built-up land, 38 percent agriculture, 50 percent forest, three percent nonforested wetlands, and less than one percent barren land, exclusive of water-covered areas. User surveys, conferences, and workshops involving 65 agencies facilitated widespread distribution of data products and produced evaluations concerning their usefulness. We found a heterogeneous user community with diverse information needs largely preferring aerial photographs rather than satellite multispectral scanner data. Among project recommendations are establishment of a network of regional land resource information centers, working toward improved compatibility of Federal, State and local information programs supportive of land use decisions.

Land use↗
NASA NTRS1980

Ecological baseline studies

Environmental studies of Merritt Island are discussed. Five areas of the island's ecology are examined. They include: a terrestrial community analyses, a plant community study, a small mammal population study, a rainfall study, and an ichthyological analyses.

Vickers, D.↗
NASA NTRS1979

Closed-ecology life support systems /CELSS/ for long-duration, manned missions

Studies were conducted to scope the principal areas of technology that can contribute to the development of closed-ecology life support systems (CELSS). Such systems may be required for future space activities, such as space stations, manufacturing facilities, or colonies. A major feature of CELSS is the regeneration of food from carbon in waste materials. Several processes, using biological and/or physico-chemical components, have been postulated for closing the recycle loop. At the present time, limits of available technical information preclude the specification of an optimum scheme. Nevertheless, the most significant technical requirements can be determined by way of an iterative procedure of formulating, evaluating and comparing various closed-system scenario. The functions features and applications of this systems engineering procedure are discussed.

Modell, M.↗
NASA NTRS1980

Life from a plantary perspective: Fundamental issues in global ecology

Twenty-three scientists from diverse disciplines met for one week at the University of California, Santa Barbara to discuss life from a planetary perspective. The scientists represented the major disciplines concerned with the Earth's biota, oceans, atmosphere and sediments, including geochemistry, atmospheric chemistry, chemical oceanography, limnology, forestry, terrestrial ecology, microbiology, biophysics, geography and remote sensing as well as mathematics. These twenty-three scientists met to discuss whether there was, at this time, a set of scientific issues concerning life and the entire Earth as a single unit, to set down the major tractable issues, and to suggest a set of activities that would promote the study of the issues identified. Their conclusions are summarized.

Botkin, D. B.↗
NASA NTRS1980

Environmental assessment for the satellite power system-concept development and evaluation program-microwave health and ecological effects

Potential health and ecological effects of the microwave beam from the microwave power transmission system (MPTS) of the satellite power system (SPS) are discussed. A detailed critical review of selected scientific articles from the published literature on the biological effects of nonionizing electromagnetic radiation is provided followed by an assessment of the possible effects of the SPS, based on exposure values for the reference system.

Source record↗
NASA NTRS1982

Sensitivity analysis as an aid in modelling and control of (poorly-defined) ecological systems

A literature review of the use of sensitivity analyses in modelling nonlinear, ill-defined systems, such as ecological interactions is presented. Discussions of previous work, and a proposed scheme for generalized sensitivity analysis applicable to ill-defined systems are included. This scheme considers classes of mathematical models, problem-defining behavior, analysis procedures (especially the use of Monte-Carlo methods), sensitivity ranking of parameters, and extension to control system design.

Hornberger, G. M.↗
NASA NTRS1981

An approach to the mathematical modelling of a controlled ecological life support system

An approach to the design of a computer based model of a closed ecological life-support system suitable for use in extraterrestrial habitats is presented. The model is based on elemental mass balance and contains representations of the metabolic activities of biological components. The model can be used as a tool in evaluating preliminary designs for closed regenerative life support systems and as a method for predicting the behavior of such systems.

Averner, M. M.↗
NASA NTRS1982

Nutritional and cultural aspects of plant species selection for a controlled ecological life support system

The feasibility of using higher plants in a controlled ecological life support system is discussed. Aspects of this system considered important in the use of higher plants include: limited energy, space, and mass, and problems relating to cultivation and management of plants, food processing, the psychological impact of vegetarian diets, and plant propagation. A total of 115 higher plant species are compared based on 21 selection criteria.

Hoff, J. E.↗