THE CASPIAN SEA LEVEL FLUCTUATIONS INFLUENCE ON THE COASTAL LANDSCAPES OF MANGISTAU AND ATYRAU REGIONS OF KAZAKHSTAN

Abstract

The article states main stages and impact of Caspian Sea level fluctuations on the north-eastern coastal landscapes (coastal area in Mangistau and Atyrau regions of Kazakhstan) for the periods of 1978 to 2014. Land cover changes and distribution of negative geo-ecological processes (salinity, flooding) were identifi ed based on the use of Landsat 1977, 1987, 1998, 2013 multispectral satellite images. Normalized Difference Water Index (NDWI) was calculated to identify the water table. On the basis of the values of brightness characteristics and synthesis of Landsat satellite images channels the article explains the correlation between vegetation and coast moisture conditions during transgressive phases and emergence of saline areas in the receding coastline. The author’s research objective was to evaluate the degree of sea level fluctuations impact (high, moderate, low) on different types of observed landscapes which have been exposed to marine transgressions in different geological epochs. As a result, the main conclusion was made that the intensity of the impact of sea level fluctuations on coastal landscapes to a large extent depends on the terrain, formed during long transgressive phases (1977–1995 years, the earliest- and late Caspian transgressions) which also connected with groundwater depth level, wind-driven waves zone of impact and the main characteristics of land cover. The author emphasizes that the study of modern areas affected by flooding will help to determine “risk flood zone” and to defi ne danger levels of areas for a different economic activities development.