Showing papers in "Mapping Sciences & Remote Sensing in 2001"

Gis erosion risk assessment of the piracicaba river basin, southeastern brazil

Abstract: Remote sensing data, a GIS, and the Universal Soil Loss Equation model (USLE) are used to develop maps of erosion risk in the Piracicaba River basin, southeastern Brazil. The mapping program was designed to determine soil erosion losses under various land uses and the extent to which land use changes affected erosion risk during 1978–1993. To evaluate the latter, the USLE model was used to simulate erosion risk during January, the highest-precipitation month, in 1978 and 1993. This made it possible to identify the areas of highest erosion risk and to develop soil/water conservation countermeasures.

Remote sensing in the recognition and mapping of tropical soils developed on topographic sequences

Abstract: The authors compare information on soil maps of the Sao Paulo region, Brazil (obtained by four different methodologies) with ground truth data and a preexisting semi-detailed soil map. The methodologies for compiling the new soil maps included: (1) conventional (field) cartographic methods; (2) air photo interpretation; (3) automated processing of radiometric data; and (4) use of radiometric data in conjunction with air photo analysis and planimetric/altimetric observations. The remote sensing methodologies produced soil maps similar to the detailed map (1) and substantially better than the pre-existing semi-detailed one. The utility of these techniques to soil surveys at rather large scales, and for tropical soil mapping in general, is assessed.

Biocomplexity and global geographic information monitoring

Abstract: The biocomplexity problem in the global “environment-society” system is examined from the point of view of the theory of complex hierarchical systems. The hierarchy of space and time scales is simulated in the terms of the quantity of information, diversity of elements, dynamic stability of biogeochemical cycles, and relations between sets of elements. A simulative-methodological model of biocomplexity dynamics based on the correlations between basic elements of the global “environment-society” system is constructed. The interrelationship among biocomplexity, stability, and viability criteria is analyzed. The possibility of computing a biocomplexity index via satellite monitoring is assessed.

Use of noaa/avhrr imagery in monitoring siberian moth outbreaks

Abstract: A large-scale outbreak of the Siberian moth (Dendrolimus sibiricus) in the forests of the Lower Angara valley region (1993-1996) was analyzed on the basis of NOAA/AVHRR imaagery. The applicability of this type of imagery for detecting the foci of damage of tree stands with the discrimination of strong (50-75%) and very strong (>75%) dying and dead trees is demonstrated. The applicability of data from a winter survey was determined by the discovery of damaged tree stands. Summer/winter images were used in demarcating the northern boundary of the focal propagation of the Siberian moth.

L-band microwave emission of forest vegetation

Abstract: Two researchers present the results of an analysis of experimental data on the characteristics of radio emission (complex permittivity of needles, leaves, branches, trunks, and canopy; crown transmissivity; total attenuation by canopy; radiobrightness temperature and emissivity of canopy and forest-surface system) of forest vegetation and individual components of the tree stand in the L-band. The results of both surface and aerial measurements are presented.

Application of multiiayer neural networks in the classification of forest types using radar imagery

Abstract: The use of multilayer neural networks for the classification of forest types on the basis of the processing of radar images is investigated. It is demonstrated by modeling that with respect to stochastic characteristics the described classification method (using multilayer neural networks) and a training procedure designed to increase its accuracy (via the a priori specification of radar reflectance values typical of specific types of vegetation) are highly effective. The methods were tested and verified using SIR-C images recorded by the U.S. Space Shuttle.

A cartographic approach for assessment of the climato-ecological state of ecosystems in the southern baykal region

Abstract: A Siberian geographer outlines the major aspects of a program to map the climatic and ecological state of ecosystems in the Lake Baykal region of southern East Siberia. A methodology for the classi...

Study of the earth's natural resources and environment on the russian segment of the international space station

Abstract: The priority tasks to be resolved using the remote sensing methods and instruments of the Russian segment of the International Space Station (ISS) are identified. In this work it is possible to use specialized instrumentation packages, developed as submodules delivered to specialized ISS modules. The specific nature of the research on remote sensing of the Earth and ecological monitoring (high speeds and volumes of the data transmitted from the station, relatively rigorous requirements for processing times, etc.) is governed by the high requirements of the surface system for the reception, processing, storage, and dissemination of space information.

Satellite monitoring of eddies and jets in the northeastern black sea

Abstract: The results of an analysis of a series of infrared images recorded by the NOAA-12 and NOAA-14 satellites (6 September-14 November 1997), making it possible to trace the formation and evolution of coastal anticyclonic eddies (CACE) between Anapa and Gagra in the northeastern Black Sea are presented. The velocity of their movement along individual segments was determined and the movement of one of the coastal eddies from the shore west of Novorossiysk and its transformation into an open-sea eddy were observed. The possible relationship between the formation and trajectory of coastal anticyclonic eddies and bottom topographic features and atmospheric influences is discussed.

Remote sensing methods for determining the bottom relief of coastal zones of seas and oceans

Abstract: The authors describe methods for determining bottom topography in continental shelf zones from remote sensing imagery. Emphasis is on methods of remotely sensing bottom relief based on the transfor...

Monitoring the subarctic front in ocean surface temperature using satellite imagery

Abstract: Surface temperature gradients, used in identifying the principal hydrological fronts of the southwestern Atlantic Ocean, were computed from charts of ocean surface temperature plotted with the use of satellite information for the period 1988–1997. An analysis is made of the seasonal variability of ocean temperature gradients in the frontal zone, as well as changes in its geographical position. The year-to-year variability of the position of the Subantarctic Front is examined.

A mathematical model of ridged-cellular and cellular sands as a basis for space image interpretation

Abstract: A mathematical model of the morphological structure of ridged-cellar and cellular sand dunes is described. This could serve as a basis for interpreting space images of similar territories on the basis of textural analysis. The basis of the model is a number of assumptions following from an analysis of the mechanism of formation of sands and files of empirical data. Dynamic modeling of the formation of the pattern of sands, confirming analytical conclusions, was carried out. A model of cellular sands was formulated on the basis of concepts concerning “dense packing” as a hexagonal grid with the use of a bivariate normal distribution.

Satellite imagery and the vertical zonation of vegetation in the mountains of southern siberia

Abstract: A method of utilizing low-resolution AVHRR imagery for the purpose of mapping and otherwise conducting an inventory of altitudinal zones of arboreal forest vegetation in mountainous areas of southern Siberia is described. Vegetation classes identified using the method are compared with those derived from more traditional field-based methods. The effects of date (season) of imaging on the accuracy of the method are discussed. Translated by Edward Torrey, Alexandria, Virginia from: Geografiya i prirodnyye resursy, 2000, No. 4, pp. 117-123.

The normalized difference vegetation index in the study of the phenology and species composition of siberian forests

Abstract: Results of an experiment for using the normalized difference vegetation index (NDVI), computed from NOAA/AVHRR images with a resolution of 8 and 1 km for studying the phenology, structure, and species composition of the taiga forests of Siberia are presented. A study is made of NDVI dynamics on the basis of 10-day values, characterizing the principal phases of the seasonal development of the forest: green wave, peak of increase in phytomass, brown wave, and leafless state. A reliable determination of the species composition of forests in two groups—coniferous and broadleaf—is possible.

Anticyclonic eddies over the northwestern continental slope in the black sea and transport of chlorophyll-rich waters into its abyssal basin

Abstract: A series of infrared NOAA satellite images of the northwestern Black Sea (resolution 1 km) and corresponding maps of chlorophyll “a” (SeaWiFS data, resolution 9 km) are analyzed for the period 1 June-28 August 1998. A major objective was detection of the movement of three synoptic-scale anticyclonic eddies over the continental slope and the entrainment of photopigment-rich coastal waters by them. The study examines the effects of wind direction on the visibility of eddies in the chlorophyll field, and attempts to identify conditions favoring the transport of chlorophyll-rich shelf waters into the sea's abyssal basin.