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At least 307 records · Page 17
All sourcesNASA NTRSDOE OSTI
NASA NTRS1972

Application of ecological, geological and oceanographic ERTS-1 imagery to Delaware's coastal resources planning

The author has identified the following significant events. Coastal vegetation species appearing in the ERTS-1 image taken of the Southern Coast of Delaware, during orbit 333 on August 16, 1972, have been correlated with ground truth vegetation maps, and imagery obtained from high altitude RB-57 and U-2 overflights. The vegetation maps of the entire Delaware Coast were prepared using data collected on foot, in small boats, and from low altitude aircraft. Multispectral analysis of high altitude RB-57 and U-2 photographs indicated that five vegetation species could be clearly discriminated from 60,000 feet altitude, including: (1) salt marsh cord grass (Spartina alterniflora); (2) salt marsh hay and spike grass (Spartina patens and Distichlis spicata); (3) reed grass (Phragmites communis); (4) high tide bush and sea myrtle (Iva species and Baccharus halimifolia); and (5) a group of fresh water species found in impounded areas built to attract water fowl. Major Spartina alterniflora and Spartina patens communities within the tidal marshes can be identified in the ERTS-1 imagery. Phragmites, and other species however, occur in smaller, more dispersed groupings and are difficult to discriminate within the resolution capability of the ERTS-1 scanner. Similarly, major impounded areas, built to attract water fowl can be detected; however, mosquito drainage ditches, covering many of Delaware's marshes, are too narrow and not long enough to be resolved by ERTS-1 sensors. High-marsh and dune communities dominated by high tide bush (Iva frutescens) and sea myrtle (Baccharus halimifolia) can be distinguished from adjacent maritime forest and beach grass communities.

Klemas, V.↗
NASA NTRS1972

The use of high altitude remote sensing in determining existing vegetation and monitoring ecological stress

High altitude color and multispectral black and white photography was used to survey existing vegetation and soil conditions on the Empire Ranch where large scale development will soon begin. Utilizing stereo pairs of the high altitude color photography, four vegetation classifications were discernable as a function of topography and foliage characteristics. In contrast to the undeveloped Ranch, the same photography was used to detect environmental changes in the Tucson metropolitan area as a result of rapid urbanization. The most prevalent change related to development is the removal of vegetation in high density areas to allow for housing starts. Erosion then occurs where vegetation has been removed.

Foster, K.↗
NASA NTRS1972

The foundations of space biology and medicine. Volume 2: Ecological and physiological bases of space biology and medicine. Part 3: Effect on the organism of dynamic flight factors. Chapter 1: Principles of gravitational biology

The physical principles of gravitation are discussed, such as gravitational and intertial forces, weight and mass, weightlessness, size and scale effects, scale limits of gravitational effects, and gravity as a biogenic factor. The behavior of the accelerative force gravitation, is described. This law proposes and quantifies the mutual gravitational attraction existing between all bodies of matter, the force being proportional to the product of masses, and inversely related to the square of the distance separating them. Gravity orientation, chronic acceleration, and hematology are examined. Systematic responses, such as circulation and renal functions, are also considered, along with animal response to a decreased acceleration field and physiology of hyper- and hypodynamic fields.

Smith, A. H.↗
NASA NTRS1972

Ecology and thermal inactivation of microbes in and on interplanetary space vehicle components

The sterilization parameters for the Viking lander of D sub 125 C = 30 minutes and z = 21 C for the exposed bioburden were derived from the experimental findings of several laboratories conducting thermal inactivation studies on Bacillus subtilis var. niger by dry heat. The moisture constraint, that the sterilizing gas shall be less than 25 percent relative humidity at standard conditions of 0 C and 760 mm Hg pressure, was added in recognition of the profound influence of water vapor on the time and temperature required for thermal inactivation of these spores. Data is presented demonstrating that the application of the moisture parameter does not significantly change the D sub 125 C and z values of 30 minutes and 21 C, respectively. Data are presented also to show the maximum influence that could be expected by decreasing the humidity to near zero percent relative humidity at 105, 113, and 125 C.

Campbell, J. E.↗
NASA NTRS1972

Central Atlantic regional ecological test site: A prototype regional environmental information system

The author has identified the following significant results. Preliminary analysis of the capabilities of ERTS-1 data in land use mapping and change detection has revealed that Level 1 land use mapping can be performed and that in some cases land use changes can be identified. Land use interpretation was accomplished with the aid of a film projection viewer and the I2S additive color viewer. By varying the filters and illumination of each spectral band it was possible to better distinguish urban areas and transportation routes. Also it enabled the toning down of signatures such as cropland and forests which on many color infrared composite photographs were washed out with strong red tints. It appears that ERTS-1 imagery is useful not only for Level 1 mapping at scales of 1:250,000 or smaller, but also for monitoring agricultural changes and locating areas of construction, when such land uses approach an area of approximately two hectares.

Alexander, R. H.↗
NASA NTRS1972

Wetlands ecology

The author has identified the following significant results. The ERTS imagery analyzed provides approximately 2/3 coverage of the test site. Analysis was made using visual methods, density slicing, and multispectral analysis. Preliminary conclusions reached are that most, if not all, of the investigation objectives can be met. Saline and near-saline wetlands can be delineated from ERTS-1 images as the wetland-upland boundaries and land-water interface are clearly defined. Major plant species or communities such as Spartina alterniflora (high and low vigor forms), Spartina patens/Distichlis spicata, and Juncus roemarianus can be discriminated and spoil disposal areas identified.

Anderson, R. R.↗
NASA NTRS1973

Ecological effects of strip mining in Ohio

The author has identified the following significant results. One result significant as a practical application and for cost benefit analysis is the relative ease with which ERTS-1 will monitor new and unclaimed stripping activities in Southeastern Ohio and in all of Appalachia. Band 5 resolution appears to be better than the often reported 80 meters. The strip mines stand out well enough to be easily identified without other graphic aids. Standing water within the strip mined area stands out in either bands 6 or 7. Areas of several acres are visible. Significant increases in surface extent of water of stripped areas should be detectable on a comparative basis. The degree of reclamation is observable in the imagery in rather gross percentage steps and for areas larger than the bare earth sizes in the table. The gradation in tones in the different bands indicates that probability density imagery using the four bands in CCT data (and statistical processing) is likely to separate degrees of vegetative reclamation.

Chase, P. E.↗
NASA NTRS1972

Microbial ecology measurement system

The sensitivity and potential rapidity of the PIA test that was demonstrated during the feasibility study warranted continuing the effort to examine the possibility of adapting this test to an automated procedure that could be used during manned missions. The effort during this program has optimized the test conditions for two important respiratory pathogens, influenza virus and Mycoplasma pneumoniae, developed a laboratory model automated detection system, and investigated a group antigen concept for virus detection. Preliminary tests on the handling of oropharygeal clinical samples for PIA testing were performed using the adenovirus system. The results obtained indicated that the PIA signal is reduced in positive samples and is increased in negative samples. Treatment with cysteine appeared to reduce nonspecific agglutination in negative samples but did not maintain the signal in positive samples.

Source record↗
NASA NTRS1972

Applications of ERTS-A Data Collection System (DCS) in the Arizona Regional Ecological Test Site (ARETS)

The author has identified the following significant results. Preliminary analysis of DCS data from the USGS Verde River stream flow measuring site indicates the DCS system is furnishing high quality data more frequently than had been expected. During the 43-day period between Nov. 3, and Dec. 15, 1972, 552 DCS transmissions were received during 193 data passes. The amount of data received far exceeded the single high quality transmission per 12-hour period expected from the DCS system. The digital-parallel ERTS-1 data has furnished sufficient to accurately compute mean daily gage heights. These in turn, are used to compute average daily streamflow rates during periods of stable or slowly changing flow conditions. The digital-parallel data has also furnished useful information during peak flow periods. However, the serial-digital DCS capability, currently under development for transmitting streamflow data, should provide data of greater utility for determining times of flood peaks.

Schumann, H. H.↗