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All sourcesNASA NTRSDOE OSTI
NASA NTRS1987

Potential application of multipolarization SAR for pine-plantation biomass estimation

This paper presents the technique and the potential utility of multipolarization Synthetic Aperture Radar (SAR) data for pine-plantation biomass estimation. Three channels of SAR data, one from the Shuttle Imaging Radar SIR-A and the other two from the aircraft SAR, were acquired over the Baldwin County, Alabama, study area. The SIR-A data were acquired with HH polarization and the aircraft SAR data with VV and VH polarizations. Linear regression techniques are used to estimate the pine-plantation biomass, tree height, and age using 21 test plots. The results indicate that the multipolarization data are highly related to the plantation biomass. The results suggest a potential application of multipolarization SAR for pine-plantation biomass estimation.

Wu, Shih-Tseng↗
NASA NTRS1988

Interpreting forest biome productivity and cover utilizing nested scales of image resolution and biogeographical analysis

The objective was to relate spectral imagery of varying resolution with ground-based data on forest productivity and cover, and to create models to predict regional estimates of forest productivity and cover with a quantifiable degree of accuracy. A three stage approach was outlined. In the first stage, a model was developed relating forest cover or productivity to TM surface reflectance values (TM/FOREST models). The TM/FOREST models were more accurate when biogeographic information regarding the landscape was either used to stratigy the landscape into more homogeneous units or incorporated directly into the TM/FOREST model. In the second stage, AVHRR/FOREST models that predicted forest cover and productivity on the basis of AVHRR band values were developed. The AVHRR/FOREST models had statistical properties similar to or better than those of the TM/FOREST models. In the third stage, the regional predictions were compared with the independent U.S. Forest Service (USFS) data. To do this regional forest cover and forest productivity maps were created using AVHRR scenes and the AVHRR/FOREST models. From the maps the county values of forest productivity and cover were calculated. It is apparent that the landscape has a strong influence on the success of the approach. An approach of using nested scales of imagery in conjunction with ground-based data can be successful in generating regional estimates of variables that are functionally related to some variable a sensor can detect.

Iverson, Louis R.↗
NASA NTRS1987

Nazareth meteorites - Classification and nomenclature

Approved names are established for the six meteorites found in Castro County, Texas; the names and classes of the specimens, which are thought to represent six separate falls, are: (1) Nazareth(a), L6; (2) Nazareth(b), L6; (3) Nazareth(c), H5; (4) Nazareth(d), H5; (5) Nazareth(e), H6; and Nazareth(iron), IIIA. Attention is given to recovery details for the six and electron microprobe analysis results for olivine and low-Ca pyroxene grains in five of the Nazareth chondrites.

Scott, Edward R. D.↗
NASA NTRS1989

Review of wildlife resources of Vandenberg Air Force Base, California

Wildlife resources are reviewed for purposes of developing a Base Biological Monitoring Program (BMP) for Vandenberg Air Force Base (VAFB) in Santa Barbara County, California. The review and recommendations were prepared by review of applicable scientific literature and environmental documents for VAFB, discussing information needs with natural resource management professionals at VAFB, and observations of base field conditions. This process found that there are 29 federally listed vertebrates (endangered, threatened, or Category 2) that occur or may occur in the vicinity of VAFB. There are also 63 other state listed or regionally declining species that may occur in the vicinity of VAFB. Habitats of VAFB represent a very valuable environmental resource for rare and declining wildlife in California. However, little information is available on VAFB wildlife resources other than lists of species that occur or are expected to occur. Recommendations are presented to initiate a long-term wildlife monitoring program at VAFB to provide information for environmental impact assessment and wise land use planning.

Breininger, David R.↗
NASA NTRS1989

Summary of 1987 and 1988 manatee aerial surveys at Kennedy Space Center

Aerial surveys of manatees conducted since 1977 at Kennedy Space Center (KSC) have provided a very useful and cost effective monitoring tool in the assessment of abundance and distribution of manatees in the northern Banana River. Data collected in the mid 1980's as part of the KSC Environmental Monitoring Program indicated that the numbers of manatees utilizing the northern Banana River had increased dramatically from earlier years and that the animals appeared to have changed their distribution patterns within the area as well (Provancha and Provancha 1988). United States Fish and Wildlife Service (USFWS) and Florida Department of Natural Resources (FLDNR) conducted bimonthly aerial surveys in 1986 for the entire Florida east coast. Their data clearly show that the Banana River has the highest concentration of manatees during the non-winter months when compared to all other segments of the east coast surveys (B. Wiegle/FLDNR, unpublished data). They further show that, in spring, an average of 71 percent of the manatees in Brevard county were located in the Banana River. During that period 85 percent of the animals were north of the NASA Causeway (State Road (SR) 402) in the KSC security zone. These data indicate the importance of the KSC waters to the Florida east coast manatee population. We reinitiated KSC surveys in 1987 to document distributions and numbers of manatees during the spring influx. Aerial censuses were continued throughout the year in 1988 and this report provides a summary of our findings for the two years.

Provancha, Jane A.↗
NASA NTRS1989

Computer-aided boundary delineation of agricultural lands

The National Agricultural Statistics Service of the United States Department of Agriculture (USDA) presently uses labor-intensive aerial photographic interpretation techniques to divide large geographical areas into manageable-sized units for estimating domestic crop and livestock production. Prototype software, the computer-aided stratification (CAS) system, was developed to automate the procedure, and currently runs on a Sun-based image processing system. With a background display of LANDSAT Thematic Mapper and United States Geological Survey Digital Line Graph data, the operator uses a cursor to delineate agricultural areas, called sampling units, which are assigned to strata of land-use and land-cover types. The resultant stratified sampling units are used as input into subsequent USDA sampling procedures. As a test, three counties in Missouri were chosen for application of the CAS procedures. Subsequent analysis indicates that CAS was five times faster in creating sampling units than the manual techniques were.

Cheng, Thomas D.↗
NASA NTRS1989

FFT-local gravimetric geoid computation

Model computations show that changes of sampling interval introduce only 0.3 cm changes, whereas zero padding provides an improvement of more than 5 cm in the fast Fourier transformation (FFT) generated geoid. For the Global Positioning System (GPS) survey of Franklin County, Ohio, the parameters selected as a result of model computations, allow large reduction in local data requirements while still retaining the cm accuracy when tapering and padding is applied. The results are shown in tables.

Nagy, Dezso↗
NASA NTRS1990

Mineral mapping at Cuprite, Nevada with a 63-channel imaging spectrometer

Geophysical and Environmental Research Imaging Spectrometer (GERIS) 63-channel scanner data covering the spectral region 0.4 to 2.5 microns were analyzed for the Cuprite mining district, Esmeralda and Nye Counties, Nevada. Individual and spatially averaged spectra extracted from the GERIS data were used to identify the minerals alunite, kaolinite, buddingtonite, and hematite by their spectral characteristics. The images were classified in the spectral domain to produce color-coded image maps of mineral distribution that clearly show the zoned nature of the hydrothermal system. Comparison of the thematic mineral maps with existing geologic and alteration maps demonstrates the utility of imaging spectrometers for producing detailed maps for mineral exploration.

Kruse, F. A.↗
NASA NTRS1990

Determining crop residue type and class using satellite acquired data

LANDSAT Thematic Mapper (TM) data for March 23, 1987 with accompanying ground truth data for the study area in Miami County, IN were used to determine crop residue type and class. Principle components and spectral ratioing transformations were applied to the LANDSAT TM data. One graphic information system (GIS) layer of land ownership was added to each original image as the eighth band of data in an attempt to improve classification. Maximum likelihood, minimum distance, and neural networks were used to classify the original, transformed, and GIS-enhanced remotely sensed data. Crop residues could be separated from one another and from bare soil and other biomass. Two types of crop residue and four classes were identified from each LANDSAT TM image. The maximum likelihood classifier performed the best classification for each original image without need of any transformation. The neural network classifier was able to improve the classification by incorporating a GIS-layer of land ownership as an eighth band of data. The maximum likelihood classifier was unable to consider this eighth band of data and thus, its results could not be improved by its consideration.

Zhuang, Xin↗
NASA NTRS1992

Influence of aerodynamic roughness length on aeolian processes: Earth, Mars, Venus

The aerodynamic roughness length (z sub 0) is the height at which a wind profile assumes a zero velocity. The lower part of the atmospheric boundary layer will be impeded by friction with the surface. An increase in surface roughness will also increase the shear stress required to initiate particle entrainment by the wind. Bagnold (1941) estimated z sub 0 as being 1/30 of the mean particle size. In Nature, surface roughness is composed of nonerodible elements as well as sand-size erodible particles. To assess z sub 0 values as a function of terrain, field experiments were conducted to obtain wind profiles monitored over natural surfaces at 15 sites in the Mojave Desert, Death Valley, and Nye County, Nevada. These sites span a variety of arid-land terrains, including smooth playas, alluvial fans, and lava flows; z sub 0 values ranged from 0.0001 cm to 1 cm. These values were incorporated in a threshold model and a flux model to assess transport efficiency over such terrains in three planetary environments (Venus, Earth, and Mars), and for particle sizes ranging from 60-500 micron. Threshold and flux are a function of planetary environment, particle density and size (Dp), and z sub 0, and the shear velocity of 1.2 x U sub *t (for Dp = 250 micron and z sub 0 = 0.84). Results show that flux on Mars is approximately 14 g/(cm x s), on Earth it is approximately 3 g/(cm x s), and on Venus 0.5 g/(cm x s). Under all planetary environments, the results also show a dramatic decrease in the flux for particles greater than 200 microns when z sub 0 increases above 0.0085 cm (corresponding to sites consisting of alluvium). When z sub 0 approaches 0.03 cm (corresponding to a mantled pahoehoe lava), the flux diminishes.

Blumberg, Dan G.↗
NASA NTRS1991

Improving classification of crop residues using digital land ownership data and Landsat TM imagery

Plant residue on the surface of cultivated soils in Miami County, Indiana is analyzed in terms of quantity and type with Landsat TM data to generate information for a conservation program for agricultural soil. The Landsat data are enhanced with land-ownership data in a geographic information system to facilitate classification with maximum-likelihood, minimum-distance, and neural-network classifiers. The most effective classifications resulted from the use of the neural network on the enhanced TM data.

Zhuang, Xin↗
NASA NTRS1991

Remanent magnetic properties of unbrecciated eucrites

This study examines the remanent magnetic properties of five unbrecciated eucrites, ranging from the coarse-grained cumulate Moore County to the quenched melt rock ALH 81001 in order to assess the strength of the magnetic field associated with their parent body during their formation. Two of the meteorites are judged as unlikely to have preserved their primary thermal remanence because of large variations in subsample remanence intensity and direction (Ibitira), and lack of NRM resistance to AF and thermal demagnetization (PCA 82502). The lack of a strong (greater than 0.01 mT) magnetizing field during their cooling on the eucrite parent body is inferred from the low normalized NRM intensities for subsamples of ALH 81001 and Yamato 791195.

Cisowski, Stanley M.↗
NASA NTRS1991

Modeling multi-frequency diurnal backscatter from a walnut orchard

The Michigan Microwave Canopy Scattering Model (MIMICS) is used to model scatterometer data that were obtained during the August 1987 EOS (Earth Observing System) synergism study. During this experiment, truck-based scatterometers were used to measure radar backscatter from a walnut orchard in Fresno County, California. Multipolarized L- and X-band data were recorded for orchard plots for which dielectric and evapotranspiration characteristics were monitored. MIMICS is used to model a multiangle data set in which a single orchard plot was observed at varying impedance angles and a series of diurnal measurements in which backscatter from this same plot was measured continuously over several 24-h periods. MIMICS accounts for variations in canopy backscatter driven by changes in canopy state that occur diurnally as well as on longer time scales. L-band backscatter is dependent not only on properties of the vegetation but also on properties of the underlying soil surface. The behavior of the X-band backscatter is dominated by properties of the tree crowns.

Mcdonald, Kyle C.↗
NASA NTRS1991

Compiling and editing agricultural strata boundaries with remotely sensed imagery and map attribute data using graphics workstations

The USDA presently uses labor-intensive photographic interpretation procedures to delineate large geographical areas into manageable size sampling units for the estimation of domestic crop and livestock production. Computer software to automate the boundary delineation procedure, called the computer-assisted stratification and sampling (CASS) system, was developed using a Hewlett Packard color-graphics workstation. The CASS procedures display Thematic Mapper (TM) satellite digital imagery on a graphics display workstation as the backdrop for the onscreen delineation of sampling units. USGS Digital Line Graph (DLG) data for roads and waterways are displayed over the TM imagery to aid in identifying potential sample unit boundaries. Initial analysis conducted with three Missouri counties indicated that CASS was six times faster than the manual techniques in delineating sampling units.

Cheng, Thomas D.↗
NASA NTRS1991

Neuro-classification of multi-type Landsat Thematic Mapper data

Neural networks have been successful in image classification and have shown potential for classifying remotely sensed data. This paper presents classifications of multitype Landsat Thematic Mapper (TM) data using neural networks. The Landsat TM Image for March 23, 1987 with accompanying ground observation data for a study area In Miami County, Indiana, U.S.A. was utilized to assess recognition of crop residues. Principal components and spectral ratio transformations were performed on the TM data. In addition, a layer of the geographic information system (GIS) for the study site was incorporated to generate GIS-enhanced TM data. This paper discusses (1) the performance of neuro-classification on each type of data, (2) how neural networks recognized each type of data as a new image and (3) comparisons of the results for each type of data obtained using neural networks, maximum likelihood, and minimum distance classifiers.

Zhuang, Xin↗
NASA NTRS1990

The Black Pearl mine, Arizona - Wolframite veins and stockscheider pegmatite related to an albitic stock

Wolframite-bearing quartz veins flanked by greisen alteration occur at and near the Black Pearl mine, Yavapai County, Arizona. The veins are genetically related to a small albitite stock, and cut a series of Proterozoic metasedimentary and intrusive rocks. The largest vein, the only one mined, is located at the apex of the stock. Field relations imply that this stock is a late-stage differentiate of time 1.4-Ga anorogenic Lawler Peak batholith, which crops out about 3 km to the south. The albitites are of igneous origin and have suffered only minor deuteric alteration. A thin (1 to 2 m) pegmatite unit ('stockscheider') occurs at the contact of the Black Pearl Albitite stock with the country rocks. Directional indicators and other evidence suggest that the pegmatite was formed in the presence of a volatile-rich fluid phase close to the time of magma emplacement. The sudden change from coarse-grained microcline-rich pegmatite to fine-grained, albite-rich albitite suggests pressure quenching, possibly due to escape of fluids up the Black Pearl vein. Stockscheider-like textures typically occur near the apical contacts of productive plutons. The presence or absence of this texture is a useful guide in prospecting for lithophile metal deposits.

Schmitz, Christopher↗
NASA NTRS1993

Carbon-14 terrestrial ages and weathering of 27 meteorites from the southern high plains and adjacent areas (USA)

We report on a series of 27 C-14 terrestrial ages of meteorites from four states in the central and southwestern U.S. These results were compared to the earlier work of Boeckl (1972). Our results showed that the weathering rate for destruction of meteorites is lower than suggested by Boeckl. We estimate a 'half-life' for removal of meteorites of about 10 to 15 ka, similar to that derived for Roosevelt County meteorites. We also studied the weathering of these meteorites compared to terrestrial age. Only a weak correlation was observed, and for these meteorites the degree of weathering can only be taken as a weak indicator of terrestrial residence time. We also measured the delta-C-13 and C-14 and amount of weathering-product carbonates which show some interesting variations with the length of time the meteorites have been exposed to weathering.

Jull, A. J. T.↗
NASA NTRS1993

The natural thermoluminescence of meteorites. VI - Carbon-14, thermoluminescence and the terrestrial ages of meteorites

A relationship is noted between the natural thermoluminescence (TL) levels and the C-14-derived terrestrial ages for meteorite finds from the U.S. Prairie States and Roosevelt County, NM; those in the Sahara are also in accord with calculated TL decay curves, for 'storage' temperatures equal to the approximate average annual temperatures at individual sites. This discussion is limited to the empirical correspondence between the two methodologies, and to theoretical decay curves for a single 'average' ordinary chondrite.

Benoit, P. H.↗