ISSN:0143-1161    

DOI:10.1080/01431168608948925

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Chemiluminescent emission from the formation of vibrationally excited OH at an altitude of approximately 85 km presents a barrier to Earth limb measurements of near-infrared emissions originating in the stratosphere. High resolution measured spectra of OH airglow in the region of interest have not been reported, and thus it is difficult to assess its impact on moderately high resolution Earth limb spectroscopy capable of looking between strong OH lines. Low resolution rocket-borne spectrometer Earth limb measurements of OH airglow arc mathematically inverted to recover vibrational state populations that are used to simulate a higher resolution spectrum in the neighbourhood of 2843cm-1, Implications for remote sensing HCI are presented.

ISSN:0143-1161    

DOI:10.1080/01431168608948926

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Various techniques as well as some general problems of agricultural remote sensing are discussed, with emphasis on the development of techniques to assess soil productivity (humus content) and the slate of crops (weediness, etc.). The techniques considered were tested in conditions of the southern part of the USSR European territory (the Ukraine, Moldavia). Applications of the technique have been exemplified.

ISSN:0143-1161    

DOI:10.1080/01431168608948927

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

A ground-truth (GT) map, produced by fieldwork and the interpretation of large-scale black and white aerial photographs, was compared with digital/graphical output from LANDSAT data of the savanna around Makurdi in central Nigeria. The GT maps were digitized, grid-converted and then aggregated while the LANDSAT data were resampled for the purpose of rectification on the ERDAS 400 microcomputer at the Michigan State University. A visual comparison of the maps was done by overlaying the digital maps on the GT map using a colour monitor while the histogram listing provided an approximate quantitative comparison.

ISSN:0143-1161    

DOI:10.1080/01431168608948928

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Reflectance variations of a stressed cotton canopy were conducted in the presence of a fan-generated air stream to investigate the effects of air movement and the resulting temperature changes on remotely-sensed data. The initial drop in reflectance after application of the air stream was found to be greatest in the morning because leaf turgor was at a maximum, enabling leaves on the windward side of the canopy to assume surprisingly stable vertical positions. This transient configuration in the morning was responsible for greater stem displacement (relative to that of the afternoon), because the leaf area normal to the air stream was maximized, thus increasing the capacity of the canopy to trap light. By afternoon, a reduction in leaf turgor was responsible for less stem displacement and consequently a reduction in light-trapping capability. However, reflectance oscillations were greater because the leaves had become sufficiently limp to flutter at the edges and about the petioles exposing both adaxial and abaxial surfaces to the incident light. The optical and thermal radiometric manifestations of this behaviour were modelled using the damped harmonic oscillator approximation by considering the canopy as a transducer for converting a mechanical response to an optical response. These relationships were combined with temperature information to derive a simple relationship for the relative entropy per radian employing thematic mapper bands 3 and 4. For a constant temperature situation the relative entropy was found to be nearly linear for both bands.

ISSN:0143-1161    

DOI:10.1080/01431168608948929

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

The canopy reflectance (CR) model for row-planted vegetation proposed earlier has been tested for soybean canopies in three different stages of growth and for corn canopies at early and full growth stages. The model fits the field-measured bidirectional CR data quite well. It is shown that, by inverting this model, one could estimate the leaf area index as well as the percentage of ground cover quite accurately from measured canopy reflectances.

ISSN:0143-1161    

DOI:10.1080/01431168608948930

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Simple regressions of single band thematic mapper simulator (TMS) reflectance data against stand basal area and leaf biomass show that the spectral feature most strongly related to vegetation amount is visible reflectance (TM bands 1, 2 and 3), which decreases as conifer basal area increases. Principal components analysis of TMS spectral data for sample stands, and stepwise multiple regression of transformed axes, showed the first principal component, interpreted as scene brightness, to be the composite spectral feature most correlated to vegetation amount. TMS data showed some ability to discriminate spectrally between coniferous forest stands dominated by different species. Dense stands of large timber dominated by red fir (Abies magnified var. shastemis) had a different average spectral reflectance from white fir (Abies concolor) dominated stands, particularly in TM bands 4 (0.76-0.90μm) and 6 (10-4-12-5μm).

ISSN:0143-1161    

DOI:10.1080/01431168608948931

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

This study evaluates the potential of measuring/mapping forest decline in spruce-fir forests using airborne NS-001 Thematic Mapper Simulator (TMS) data. Using field instruments, it was found that ratios of 1.65/1.23 and 1 65/083 μm reflectance discriminated between spruce samples of low and high damage sites. Using TMS data, 1.65/1.23 and 1 65/0.83 μm band ratios were found to be strongly correlated with ground-based measurements of forest damage. Ratio colour density slice images using 1.65/1.23 or 1.65/0.83μm band ratios, and images using 0.56μ and 1.65μm bands with either of these band ratios in a false colour composite, provide accurate means of detecting, quantifying and mapping levels of forest decline. Using these techniques, new areas of forest decline have been detected, and monitoring of forest decline will be possible.

ISSN:0143-1161    

DOI:10.1080/01431168608948932

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

The multi-spectral method for atmospheric corrections is investigated. The analysis shows that the non-linear effects of the atmospheric absorption can be accounted for by using three channels. The results clarify and lend theoretical support to previous works. A simple correction procedure is proposed. In the case where channel 3 of the NOAA AVHRR is not available or is contaminated, simultaneous METEOSAT infrared data can be used instead. The result tested with in situ measured temperatures shows a marked improvement when three channels are used. In this procedure, the detailed knowledge of the local atmospheric profiles is not required.

ISSN:0143-1161    

DOI:10.1080/01431168608948933

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

A snow survey in northwest China has been carried out using meteorological satellite NOAA-7 images. A two-step geometric rectification method is presented. The first step involves a large-scale geometric rectification and the second step concentrates on a small area of interest by using the control point rectification method. A high precision of geometric rectification can be achieved using this approach. The snow covered area in the Qilian Mountain Basin is calculated.

ISSN:0143-1161    

DOI:10.1080/01431168608948934

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor