Принципы составления карты растительности европейско-западносибирских тундр м. 1 : 7 500 000

Abstract

The tundras of East Europe and West Siberia occupy a vast region in the Russian North. This region is ranked as a separate province within the subzones of arctic and subarctic tundras. The European and West Siberian parts of it have many essential features in common: the synchronous alternation of sea transgressions and glaciations, predominantly plain relief with a great thickness of quaternary deposits, humidity of climate, which result in similar vegetation structure and species composition. It seems possible to develope an uniform approach to the problem of spatial differentiation of their plant cover and its reflection on a small-scale (1 : 7 500 000) geobotanical map. The creation of a new survey vegetation map is a complicated and labour-consuming task that needs the analysis and generalization of all the available facts at new level of knowledge. The main factors of spatial differentiation of tundra vegetation are climatic zonation, regional histiory and landscape geomorphology. A fragment of the legend is demonstrated on table 1. The column 1 shows the regional position along with genesis of a mapping unit. The scale allows to reflect the zonal features of vegetation in sufficient detail through the community composition of a prevailing syntaxon (column 2). In column 3 dominant and differential species are listed. The configuration of the mapping categories, their extension and pattern are defined by the macrorelief. The specific features of landscape geomorphology are given in column 4 and the elevation above sea-level – in column 5. The structure of mapping units are illustrated by aerial or remote sensing images (column 6). In column 8 the spectra of communities ecologically replacing one another in different environments are presented. These communities are shown by conditional symbols, their deciphering being given in additional textual legend (table 2). At the end of the article the types of data are listed that should be used at small-scale (1 : 7 500 000) mapping of tundra vegetation: I) map schemes of the zonal and subzonal subdivision of plant cover; 2) schemes of regional differentiation; 3) typological geobotanical maps at 1 : 1 500 000 – 1 : 4 000 000 scale; 4) géomorphologie or landscape maps at 1 : 4 000 000 scale or less; 5) hypsometric maps of the same scale range; 6) large-scale and middle-scale geobotanical maps of the key regions; 7) aerial and space images of 1 : 200 000 – 1 : 100 000 scale; 8) maps of the geographic distribution of differential species.