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Abstract  

Recent advances in the power and capabilities of personal computers have brought the algorithms and representational methods of Geographic Information Systems (GIS) to the desktop. Information that has relationships between elements may be represented spatially, especially if some distance metric can be brought to bear. This paper discusses information cartography, the use of spatial methods for the display of non-Geographic data.

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Abstract  

Recent advances in the power and capabilities of personal computers have brought the algorithms and representational methods of Geographic Information Systems (GIS) to the desktop. Information that has relationships between elements may be represented spatially, especially if some distance metric can be brought to bear. This paper discusses information cartography, the use of spatial methods for the display of non-Geographic data.

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We propose a method that has general relevance to the digital representation of spatial variation of multivariate landscape data. It is based on the average similarity that operational geographic units (OGU) have with the adjacent ones according to characters relevant understanding landscape patterns and dynamics. The method is flexible and easily executable within the technological framework of geographic information systems (GIS) that today is available even free of charge or at very low cost. An example shows how the method, applied to spatial data of a floristic project for the urban area of Trieste (NE-Italy), can identify floristically homogeneous patches and can quantify the heterogeneity of the transition zones between such patches.

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Cereal Research Communications
Authors: Norbert Schlang, Ulrike Steiner, Heinz-Wilhelm Dehne, Jiro Murakami, Etienne Duveiller, and Erich-Christian Oerke

Fusarium Head Blight (FHB) is one the most important diseases in small grain cereals and often is caused by a complex of Fusarium species. Some of these species are able to produce one or several mycotoxins. The spatial distribution of the disease and associated mycotoxins was examined in this study. Results were mapped and analysed with a geographic information system (GIS). Correlations between the incidence of the deoxynivalenol (DON) producing Fusarium species and DON contamination of kernels were rather weak. The level of DON contamination seemed to be less influenced by the frequency of DON producing Fusarium species than by other factors.

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Deterministic seismic hazard computations were performed along four different profiles across the downtown of Budapest. Synthetic seismograms were computed by the so called “hybrid technique”. By applying the hybrid technique it is possible to take into account the focal source, the path and the site effect together. Four independent computations have been performed using the same seismic source but different profiles. The parameters of the seismic source were adopted from the parameters of the well-known 1956 Dunaharaszti earthquake. The focal mechanism and the homogeneous and heterogeneous parts of the profiles are known from geophysical and geological data of the investigated area.As the results of the computations PGA (peak ground acceleration) grid maps of the downtown of Budapest for the three different components came into existence. Furthermore spectral acceleration (response spectra, SA) and RSR charts of the synthetic seismograms for the four different profiles were created. The PGA grid maps show that the maximal PGA values are situated at the eastern (Pest) part of the downtown, and their values are 50–200 cm/s 2 .For the downtown of Budapest a special seismic risk map have been prepared. This special seismic risk map were created on the basis of the difference between the maximal amplitude frequencies of SA of synthetic seismograms and the building’s eigenfrequencies at every 0.1 km 2 of the downtown. In order to determine the building’s eigenfrequencies microseismic noise measurement were performed at 6 different buildings in the downtown. The special seismic risk map shows that the buildings situated at the hilly western section of the downtown have higher seismic risk than the ones at the flat eastern part.

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Abstract  

A device was developed for the collection, containment, and bubbling of radon from groundwater samples to facilitate concentration measurements in the field without the need for fragile glassware. Wellwater supplies were collected in high-potential areas of New York State in a comparison of the device with traditional methods (liquid scintillation and laboratory-based Lucas-cell counters). Waterborne radon levels to 4100 Bq L–1 reveal the potential contribution to indoor air from everyday water use in a home, as levels of 1500 Bq L–1 contribute about 150 Bq m–3 (the EPA-recommended limit) to indoor-air radon levels. With a Geographic Information System (GIS), spatial coordinates from each site are used to correlate concentrations with bedrock geology.

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The aim of our study is to determine the design ground acceleration values at the whole territory of Debrecen and to accomplish the seismic risk map of Debrecen using synthetic seismograms. Synthetic seismograms are computed by the so called ``hybrid technique" along 11 different profiles crossing the city. The hybrid technique consists of the modal summation method, followed by finite difference modelling. 11 independent computations have been performed using the same seismic source but different profiles. The seismic source has been located in the so called “Mobile Zone”, which is a seismically active fault system in Érmellék region. The focal mechanism and the homogeneous and heterogeneous parts of the profiles are  known from geophysical and geological data of the investigated area. As the results of the computations PGA grid maps of Debrecen for the 3 different components and the spectral  acceleration (response spectra, SA) charts of the synthetic seismograms for the transversal components came  into existence. The seismic risk map of the city has been completed from the SA charts created from the synthetic seismograms and from the grid map of the buildings in Debrecen with different number of floors by applying GIS tools.

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Abstract  

This is the first systematic study of air pollution from heavy metals and other trace elements throughout several industrialized areas and national parks of Eastern Romanian Carpathians using the moss biomonitoring technique. Samples ofHylocomium splendens collected at 120 sites were analyzed by epithermal neutron activation analysis at the pulsed fast reactor IBR-2 at JINR, Dubna, for a wide range of elements including heavy metals and rare earths (Na, Mg, Al, Cl,K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni (by (n,p) reaction), Cu, Zn, As, Se, Br, Rb, Sr, Zr, Mo, Ag, Sn, Sb, I, Cs, Ba, La, Ce, Nd, Sm, Eu, Gd, Tb, Yb, Hf, Ta, W, Au, Th, and U). Copper, lead and cadmium were determined by AAS. Certified Reference Standards of mosses produced for interlaboratory comparisons in the European moss-survey 1995 were used to ensure the quality of the measurements. To present results in the form of coloured contour maps the geographical information system GIS-INTEGRO was used. The regional extent of pollution with specific metals was determined. Results reported are well consistent with those obtained in numerous recent projects carried out in Germany, the Netherlands, Poland, Bulgaria and other countries.

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Multi-band remotely sensed image data contain information on landscape pattern and temporal changes that are greatly underutilized in this technological era when monitoring of disturbance and ecological dynamics is increasingly important to address questions regarding sustainability of ecosystem health and climate change. Among the reasons for this loss of analytical opportunity are the inadequacy of methods for systematic extraction of pattern elements, incongruity between information paradigms for remote sensing and geographic information systems (GIS), and the sheer volume of remotely sensed image data when acquired regularly over time. Long-term cooperative landscape ecological investigations concerning habitat and change detection in conjunction with remote sensing and GIS have yielded a pattern-based approach to progressively segmenting images (PSI) that culminates in a doubly segmented image representation by sets of approximating signal vectors that serve as parsimonious proxies for pixel vectors. The coarser level of segmentation is entirely congruent with raster map structures for GIS, and yet mimics the appearance of an image display by colorization using information on typical spectral properties of segments contained in attribute tables. The components of the coarser representation as spatial segments constitute explicit elements of pattern at several levels. The explicit nature of these pattern elements enables spatial pattern matching for change detection that resolves difficulties with phenological variability and continuity of sensor configurations over time. Conversion to segmented representation can be applied to multi-temporal change indices so as to elicit longer-term patterns of change from temporal sequences of images. The finer level of segmentation for spectral detail enables restoration of image bands in the manner of a low-pass filter for analysis according to the usual paradigms of remote sensing. Mapping of the residuals for the finer detail of image approximation provides further information on exceptional features of landscape ecological pattern.

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We suggest a classificatory approach for land cover analysis that integrates fuzzy set theory with permutation techniques. It represents a non parametric alternative and/or a complement of traditional multivariate statistics when data are scarce, missing, burdened with high degree of uncertainty and originated from different sources and/or times. According to this approach, the Operational Geographic Units (OGUs) in which landscape is subdivided and sampled are classified with hierarchical clustering methods. The clusters of a classification which are significantly sharp are used to define fuzzy sets. In this way, the original data scores are transformed by degrees of belonging. We introduce the concepts of endogenous and exogenous fuzzy sets and we suggest to apply the Mantel test between the similarity matrices of these fuzzy sets to test the predictivity of internal variables with respect to external variables. The approach is applied to OGUs corresponding to the smallest administrative units (kebeles) of the Ethiopian Rift Valley, a degrading area with high risk of further degradation. We found that: 1) there is a high correlation between geo-physical features of the landscape (geology, rainfall and elevation) and some indicators of the human pressure such as land use/cover, land management for livestock breeding and human, household and livestock densities, 2) there is a high correlation between land degradation, measured with relative loss of Normalized Difference Vegetation Index (NDVI) and the human pressure. However, the correlation is higher when the human pressure is considered in the geo-physical context of the landscape. The approach can be easily applied to produce maps useful for planning purposes thanks to geographical information system (GIS) technology that is becoming available at low cost even to small administrative units of developing countries.

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