The GRACE gravity satellite mission has provided monthly gravity field solutions for about 15 years enabling a unique opportunity to monitor large scale mass variation processes. By the end of the GRACE, the GRACE-FO mission was launched in order to continue the time series of monthly gravity fields. The two missions are similar in most aspects apart from the improved intersatellite range rate measurements, which is performed with lasers in addition to microwaves. An obvious demand for the geoscientific applications of the monthly gravity field models is to understand the consistency of the models provided by the two missions. This study provides a case-study related consistency investigation of GRACE and GRACE-FO monthly solutions for the Aral Sea region. As the closeness of the Caspian Sea may influence the monthly mass variations of the Aral Sea, it has also been involved in the investigations. According to the results, GRACE-FO models seem to continue the mass variations of the GRACE period properly, therefore their use jointly with GRACE is suggested. Based on the justified characteristics of the gravity anomaly by water volume variations in the case of the Aral Sea, GRACE models for the period March–June 2017 are suggested to be neglected. Though the correlation between water volume and monthly gravity field variations is convincing in the case of the Aral Sea, no such a correlation for the Caspian Sea could have been detected, which suggests to be the consequence of other mass varying processes, may be related to the seismicity of the Caspian Sea area.

The work concerns the application of spectral indexes (NDVI, SAVI and other types of spectral indexes) for monitoring and evaluation of the plant communities of desertified Amudarya river delta plant communities. The described approach includes the multi-level spatial model of the landscape transformation with desertification, soil erosion, soil salinity increasing, climatic changes to improve the adequacy of the remote sensing methods for complicated and non-stable post-deltaic ecosystems of the Aral Sea region. The key role of the geomorphological and pedological analysis for the spatial model implementation had been shown. Some geostatistical techniques had been used to link general data on vegetation cover calculated from remote sensing information with the type of the plant community, with consequent clarification of the vegetation map using both succession-based model approaches and field data.

The paper concerns effect of micro-focal processes of landscape transformation in desertified deltas in th arid zone. Some particular stages of the pant community succession had been revealed. Genetic link of these transformation with complex terrestrial ecosystem degradation had been derived.

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The article discusses the results of the study of sandy deserts, which allowed us to obtain and reveal a number of important laws and mechanisms of formation, formation, movement and development of Aeolian landforms. The establishment of these patterns helps to solve a number of practical tasks to combat sand drifts in the sandy desert of various objects. In connection with the prospects for the development of this territory, it is very important to know the direction and intensity of the development of these processes. The obtained data on the mechanism and structure of the entire air-soil flow, starting from the moment of its formation, i.e. in the blowing zone, and ending with the transfer and deposition of soil particles by wind in the accumulation zone, make it possible to increase the level of scientific validity of the rational use of soil resources, as well as to take timely measures to protect the environment.