Methods of Thematic Map Comparison

A procedure for estimating hydrological parameters is presented which combines a) remote sensing and GIS techniques with b) data extracted from site visits to city districts; the estimate so obtained is compared with estimates from rainfall data. It is developed in urban sub-basins of Dilúvio Basin in the metropolitan region of Porto Alegre, Brazil. A Fuzzy Algorithm which performs within sub-pixel level is used. Cover classes studied are: highly and slightly impervious, bare ground, grassed open space, and forest. A soil thematic map is determined based on pedological studies. A final distributed thematic map of potential runoff is obtained by superimposing previous data. It is compared with lumped runoff potential from rainfall events in sub-basins. These broad multi-source data hold basic information to develop an alternative strategy for hydrologic studies in urban basins.

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Mapping mountain geosystems and their damage in Еаstern Transbaikalia

Geodesy and Cartography ◽

10.22389/0016-7126-2019-944-2-22-31 ◽

2019 ◽

Vol 944 (2) ◽

pp. 22-31

Author(s):

S.A. Sedykh

Keyword(s):

Ecological Study ◽

Thematic Map ◽

Western Transbaikalia ◽

Semiotic Approach

The author presents the results of the ecological study, with the analysis of landscapes and mapping the area of the 73 km2 polygon. The polygon is located in Western Transbaikalia, covering the site of the Chikoy basin and its mountainous frame. For the analysis of the structure of geosystems and the estimation of the damage, the basic geosystem approach is applied to modern geoinformation-cartographic and remote methods. The carto-semiotic approach was used to visualize and complete the thematic map. A landscape typological map was created in the scale of 1

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High-Density Genetic Map Construction and Identification of QTLs Controlling Leaf Abscission Trait in Poncirus trifoliata

International Journal of Molecular Sciences ◽

10.3390/ijms22115723 ◽

2021 ◽

Vol 22 (11) ◽

pp. 5723

Author(s):

Yuan-Yuan Xu ◽

Sheng-Rui Liu ◽

Zhi-Meng Gan ◽

Ren-Fang Zeng ◽

Jin-Zhi Zhang ◽

...

Keyword(s):

Qtl Mapping ◽

Linkage Map ◽

Genetic Map ◽

Expression Patterns ◽

High Density ◽

Poncirus Trifoliata ◽

Leaf Abscission ◽

Comparative Genomic ◽

Map Comparison ◽

Genomic Studies

A high-density genetic linkage map is essential for genetic and genomic studies including QTL mapping, genome assembly, and comparative genomic analysis. Here, we constructed a citrus high-density linkage map using SSR and SNP markers, which are evenly distributed across the citrus genome. The integrated linkage map contains 4163 markers with an average distance of 1.12 cM. The female and male linkage maps contain 1478 and 2976 markers with genetic lengths of 1093.90 cM and 1227.03 cM, respectively. Meanwhile, a genetic map comparison demonstrates that the linear order of common markers is highly conserved between the clementine mandarin and Poncirus trifoliata. Based on this high-density integrated citrus genetic map and two years of deciduous phenotypic data, two loci conferring leaf abscission phenotypic variation were detected on scaffold 1 (including 36 genes) and scaffold 8 (including 107 genes) using association analysis. Moreover, the expression patterns of 30 candidate genes were investigated under cold stress conditions because cold temperature is closely linked with the deciduous trait. The developed high-density genetic map will facilitate QTL mapping and genomic studies, and the localization of the leaf abscission deciduous trait will be valuable for understanding the mechanism of this deciduous trait and citrus breeding.

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Conveying map finesse: thematic map making essentials for today’s university students

Journal of Geography in Higher Education ◽

10.1080/03098265.2020.1850656 ◽

2020 ◽

pp. 1-27

Author(s):

Gertrud Schaab ◽

Sybil Adams ◽

Serena Coetzee

Keyword(s):

University Students ◽

Thematic Map

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Quantitative Assessment for Detection and Monitoring of Coastline Dynamics with Temporal RADARSAT Images

Remote Sensing ◽

10.3390/rs10111705 ◽

2018 ◽

Vol 10 (11) ◽

pp. 1705 ◽

Cited By ~ 2

Author(s):

Biswajeet Pradhan ◽

Hossein Rizeei ◽

Abdinur Abdulle

Keyword(s):

Noise Removal ◽

Synthetic Aperture ◽

Support Vector ◽

Spectral Difference ◽

Sar Images ◽

Thematic Map ◽

Tropical Regions ◽

Passive Sensor ◽

Multiresolution Segmentation ◽

Salt And Pepper

This study aims to detect coastline changes using temporal synthetic aperture radar (SAR) images for the state of Kelantan, Malaysia. Two active images, namely, RADARSAT-1 captured in 2003 and RADARSAT-2 captured in 2014, were used to monitor such changes. We applied noise removal and edge detection filtering on RADARSAT images for preprocessing to remove salt and pepper distortion. Different segmentation analyses were also applied to the filtered images. Firstly, multiresolution segmentation, maximum spectral difference and chessboard segmentation were performed to separate land pixels from ocean ones. Next, the Taguchi method was used to optimise segmentation parameters. Subsequently, a support vector machine algorithm was applied on the optimised segments to classify shorelines with an accuracy of 98% for both temporal images. Results were validated using a thematic map from the Department of Survey and Mapping of Malaysia. The change detection showed an average difference in the shoreline of 12.5 m between 2003 and 2014. The methods developed in this study demonstrate the ability of active SAR sensors to map and detect shoreline changes, especially during low or high tides in tropical regions where passive sensor imagery is often masked by clouds.

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SuperDARN convection and Sondrestrom plasma drift

Annales Geophysicae ◽

10.5194/angeo-19-749-2001 ◽

2001 ◽

Vol 19 (7) ◽

pp. 749-759 ◽

Cited By ~ 21

Author(s):

L. Xu ◽

A. V. Koustov ◽

J. Thayer ◽

M. A. McCready

Keyword(s):

Reasonable Agreement ◽

Temporal Variations ◽

Line Of Sight ◽

Data Sets ◽

Plasma Convection ◽

Map Comparison ◽

Incoherent Scatter ◽

Plasma Drift ◽

End Products ◽

Strong Disagreement

Abstract. Plasma convection measurements by the Goose Bay and Stokkseyri SuperDARN radar pair and the Sondrestrom incoherent scatter radar are compared in three different ways, by looking at the line-of-sight (l-o-s) velocities, by comparing the SuperDARN vectors and corresponding Sondrestrom l-o-s velocities and by comparing the end products of the instruments, the convection maps. All three comparisons show overall reasonable agreement of the convection measurements though the data spread is significant and for some points a strong disagreement is obvious. The convection map comparison shows a tendency for the SuperDARN velocities to be often less than the Sondrestrom drifts for strong flows (velocities > 1000 m/s) and larger for weak flows (velocities < 500 m/s). On average, both effects do not exceed 35%. Data indicate that inconsistencies between the two data sets occur largely at times of fast temporal variations of the plasma drift and for strongly irregular flow ac-cording to the SuperDARN convection maps. These facts indicate that the observed discrepancies are in many cases a result of the different spatial and temporal resolutions of the instruments.Key words. Ionosphere (ionospheric irregularities; plasma convection; polar ionosphere)

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