ISSN:0143-1161    

DOI:10.1080/01431169008955012

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

A remotely-sensed image represents natural objects with irregular shapes, some of which have fractal properties. During data processing the most often used methods of determining the fractal dimension are analysed according to objects of known dimension. A new method which improves the accuracy of previous techniques is then presented. This process can be used for specific applications in remote sensing; on the one hand for the determination of the dimension of natural reliefs observed from a satellite and on the other hand for the analysis of the degree of decay of diseased trees observed in aerial photographs.

ISSN:0143-1161    

DOI:10.1080/01431169008955013

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

An automated system has been developed for mosaicking spaceborne synthetic aperture radar (SAR) imagery. The system is capable of producing multiframe mosaics for large-scale mapping by combining images in both the along-track direction and adjacent cross-track swaths from ascending and descending passes. The system requires no operator interaction and is capable of achieving high registration accuracy. The output product is a geocoded mosaic on a standard map grid such as UTM or polar stereographic. The procedure described in detail in this paper consists essentially of remapping the individual image frames into these standard grids, frame-to-frame image registration and radiometric smoothing of the seams. These procedures are directly applicable to both the Magellan Venus Mapper and a scanning SAR design such as Radarsat, Eos SAR in addition to merging image frames from traditional SAR systems such as SEASAT and SIR-B. With minor modifications, it may also be applied to spaceborne optical sensor data to generate large-scale mosaics efficiently and with a high degree of accuracy. The system has been tested with SEASAT, SIR-B and Landsat TM data. Examples presented in this paper include a 38-frame mosaic of the Yukon River basin in central Alaska, a 33-frame mosaic of southern California and a three-frame terrain-corrected geocoded mosaic of the Wind River basin in Wyoming.

ISSN:0143-1161    

DOI:10.1080/01431169008955014

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

The potential of SPOT Multispectral (XS) and Landsat Multispectral Scanner (MSS) for automatically outlining agricultural near-urban interfaces, by means of classifications, was tested for a study area around Yogyakarta, Central Java. Photo-interpretation of SPOT panchromatic (P) images and aerial photographs acquired during the past 20 years was used as a reference to evaluate maps derived from SPOT XS and Landsat MSS and to quantify the evolution of this area. SPOT XS mapping proved to be reliable, whereas only overall information could be derived from Landsat. Due to the usual heterogeneity of the Javanese landscapes and to the present unavailability of locally-adapted lextural classifiers, the visual analysis of SPOT P images provided better results than the digital processing of SPOT XS data.

ISSN:0143-1161    

DOI:10.1080/01431169008955015

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

The relative net photosynthetic activity of crop, grass and woodland areas was estimated from airborne eddy correlation carbon dioxide flux density measurements for various transects within a 100 km by 300 km agricultural region in southern Manitoba. Landsat Multispectral Scanner (MSS) data were used to estimate the density and vegetation class boundaries associated with these measurements. The airborne carbon dioxide flux measurements were made during good growing conditions, namely with soil moisture reserves (> 50 per cent field capacity), high radiation (950 W/m2), cloudless skies and warm air temperature (> 25°C). The carbon dioxide flux ranged from (a) -20 to -35 kg CO2ha−1h−1for the heavy crop canopies of the cereal and oilseed growing areas located on the clay and clay loam soils, (b) -12 to -25kg CO2ha−1h−1for the mixed crop grassland and dense woodlands on loam to sandy loam soils and (c) -8 to - 15 kg CO2ha−1h−1for the mixed grassland areas on sandy loam to sandy soils. Indices calculated from Landsat bands 5 and 6 (red and near-infrared) were used to quantify the distribution of green vegetation. A large area relative photosynthetic index (LARPS), which is a measure of the carbon dioxide flux per vegetative greenness unit, is proposed as a parameter which represents the effectiveness of chlorophyll's ability to absorb carbon dioxide.

ISSN:0143-1161    

DOI:10.1080/01431169008955016

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

In the Spitsbergen region (78°N), field radiometer measurements were collected from training zones considered to be representative of different lithological units and compared with the corresponding SPOT multispectral digital values. Correlations between field measurements and remotely-sensed data have been established, as well as the SPOT XS3 sensor's dependence on the solar zenith angle. On the basis of the relations between the field and satellite data, the boundaries between the different lithological units obtained from illuminated slopes can be extended into shaded zones.

ISSN:0143-1161    

DOI:10.1080/01431169008955017

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

The visual interpretation and digital image analysis of remotely-sensed data of parts of the Lalitpur district of Uttar Pradesh have enabled the identification of an area having scattered remnants of Deccan Trap basic volcanic rocks occurring in the form of mesas associated with its weathered derivatives, laterite and typical black cotton soil. The lithology of the borehole data from the study area and the presence of characteristic black cotton soil cover marked by extensive gully development confirms the occurrence of volcanic ‘traps’ overlying the Pre Cambrian Bundelkhand Granite. This finding strengthens the earlier postulation by Vredenburg that the Deccan Trap extended far to the north in the Bundelkhand region. The interpretation of remotely-sensed data has also helped in delineating the boundary lineaments. Further, the present study has revealed that hitherto unknown bounding lineaments of the study area identified through satellite remote sensing and the abrupt termination of quartz reefs in the northern extremity of the area, suggest block faulting leading to the preservation of Deccan Trap rocks which might otherwise have remained exposed and been eroded.

ISSN:0143-1161    

DOI:10.1080/01431169008955018

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

This note is based on observations and interpretations of aerial photographs. Aerial photocharacters such as tonal differences, texture, shape, size, form, pattern, vegetation and associated features were considered in identifying the geomorphological features: lineaments, terraces, reefs, beaches, beach rock, erosion, turbidity, etc. The island relief is predominantly mountainous with granitic cliffs and rugged peaks. Rocky shores of the island alternate with beach accumulations. Lineaments correspond with the regional trend of the rock exposures. There are three to four levels of terraces, reefs are common along the shores, beaches occur mostly in protected bays and beach rock has been observed at several localities. Based on the disposition of landforms it is surmised that the coastal features are controlled by the regional structures and erosion is more common than the progradation, especially on the west coast.

ISSN:0143-1161    

DOI:10.1080/01431169008955019

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

Eutrophication, or enrichment, of the natural water in New Jersey's coastal waters has an adverse impact on the economic welfare of the state. Since shipboard sampling is not cost-effective for providing data on coastal'estuarine water processes and materials, satellite remote sensing, with its synoptic and repetitive coverage, is used to obtain some of the data for eutrophication-related water quality analysis. For the purpose of this study, existing Landsat-5 Thematic Mapper digital data, acquired on 1 September 1985, along with the sea truth observations, were obtained for quantitative analysis, The goal was to establish a correlation between total plankton content and remote sensing signals indicating the relative degree of eutrophy and productivity in New Jersey's coastal waters.

ISSN:0143-1161    

DOI:10.1080/01431169008955020

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

A multi-temporal study of chlorophyll-a concentration, has been made by means of Landsat-5 Thematic Mapper (TM) band 1 (0·45-0·52μm) in the Albufera of Valencia, a hypertrophic lagoon of shallow depth. The relationship between this parameter and satellite data was set up from in situ measurements and concurrent satellite data obtained in a campaign from 22 July 1985. This relation has been applied to images of different dates by using a simple procedure of correction, which is based on the use of selected surfaces whose ground reflectance is assumed to be constant with time. Good results were obtained and chlorophyll-a concentrations have been determined with an error of 20 per cent.

ISSN:0143-1161    

DOI:10.1080/01431169008955021

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor