in 1969-2009
The main idea of the practical exercise
Before going into the main research of the future development trends of the Aydar- Arnasay lakes system (AALS), we should analyze how this system has been evolving since 1969. In particular, according to one of the established objectives of the research, we will investigate how the water-surface and volume of the AALS have been changing. For this reason, it has been decided to calculate the AALS water-surface area starting from 1969 to present time.
It should be emphasized that finding of the valid method for the calculation was one of the intractable questions in the exercise. Generally speaking, four main GIS methods were found for the calculation of the AALS water-surface area:
Comparative method based on the analysis of the different land use datasets by Arcview program;
Comparative method based on the analysis of the USSR military maps using Google Earth and the Arcview program;
CEU eTD Collection
Using of Digital Elevation Maps (DEM) in the Arcview program;
Remote sensing provided by the MultiSpec program.
It can be observed that all methods in this exercise were based on application of the modern GIS technologies which are an effective tool for investigation of various environmental issues10. However, in the course of the exercise it was identified that three of them has the rigid limitations that make the calculation of the parameters concerned impossible. In order to show the whole process of exercise accomplishment, we consider it necessary to go step by step describing the basic ideas and limitations of the methods used.
10 See section 2.3.4
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