Drought is one of the most damaging environmental hazards and a naturally occurring phenomenon in Central Asia that is accompanied by crucial consequences for the agriculture sector. This research aimed at understanding the nature and extent of drought over the cropland regions of Central Asia with the help of spatiotemporal information from the region. We assessed drought occurrence using the vegetation health index (VHI). An algorithm was developed to reduce the noise of heterogeneous land surfaces by adjusting the vegetation index and brightness temperature. The vegetation condition index (VCI) and temperature condition index (TCI) were calculated using Moderate Resolution Imaging Spectroradiometer (MODIS) products for the growing season (April–September) from 2000 to 2015. The intense drought years were identified and a drought map (drought probability occurrence) was generated. The findings of this research indicated regional heterogeneity in the cropland areas having experienced droughts, observed through spatiotemporal variations. Some of the rain-fed and irrigated croplands of Kazakhstan demonstrated a higher vulnerability to annual drought occurrences and climate change impacts, while other cropland regions were found to be more resistant to such changes. The development of policy tools is required to support informed decision-making and planning processes to adapt to the occurrence of droughts. This could be achieved by the timely assessment, monitoring, and evaluation of the spatiotemporal distribution trends and variabilities of drought occurrences in this region. The results from this study focus on the spatiotemporal variations in drought to reveal the bigger picture in order to better understand the regional capacity for sustainable land management and agricultural activities within a changing environment.

The study of the transformation of natural complexes in areas with a developed infrastructure for oil subsurface use is a prerequisite condition for solving the environmental problems of oil-producing regions. Located in the territory of the Atyrau Region in Western Kazakhstan, the Tengiz oil field is one of the largest oil fields in the world. The field has been under intensive development for more than 40 years and is characterised by a large volume of anthropogenic load, which contributes to a significant transformation of the landscape complex. The purpose of this study is to investigate the dynamics of landscape changes in the territory of the Tengiz field and to assess its ecological condition. Based on the materials from many years of research, the features of the Tengiz field and the main technogenic sources affecting the landscape complex were identified. Several quantitative indicators characterising the anthropogenic load were calculated based on satellite images. On the basis of Landsat – 5 TM, 7 ETM+ and 8 OLI and Sentinel-2A (S2A) data, the vegetation index of land cover was calculated using normalised difference vegetation index (NDVI), demonstrating the dynamics of landscape changes in the period from 1990 to 2020. The obtained results show that the areas of some landscape components continue to deteriorate. For example, the area of open soil in 2020 decreased due to the withdrawal of these areas for industrial facilities, which increased by 2.2 times by 2020 due to intensive field development. This study demonstrates the importance of monitoring and studying desert landscape complexes under active anthropogenic impact to ensure the sustainable development of territories.

Since 1960, water level began to decline considerably due to anthropogenic impact of the Aral Sea (AS), and it is continued to this day, which has led to dramatic changes in the climate around the AS, including ambient temperatures and sharp increases in evapotranspiration. Although, it isn't possible to see normal trend in this precipitation. Time series analysis of the FTI (First Time Interval 1901-1960) and STI (Second Time Interval, 1960-2015), highlighting climate change around the AS, based on Global Climate Data, suggests that there is a significant negative difference between precipitation and evapotranspiration during the drying of the AS. It is possible to see the logical compatibility of the air temperature and difference between precipitation and evapotranspiration observed around the AS, i.e. the temperature fluctuation trend is positive and contrary to the difference between precipitation and evapotranspiration negative trend, which means that the annual hydrological budget was reduced according to the time scale. In this article, determining the AS as the central point, we analyze the changes in the thermal and hydrological processes observed on the AS, as well as the impact to the environment of anomalous climate change observed on and around the sea like the drying out of the AS.

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