The paper presents the range and applications of thematic tasks for ultra-high spatial resolution data from small unmanned aerial vehicles (UAVs) in the integral system of environmental multi-platform and multi-scaled monitoring of Lake Sevan, which is one of the greatest freshwater lakes in Eurasia. From the 1930s, it had been subjected to human-driven changing of the water level with associated and currently exacerbated environmental issues. We elaborated the specific techniques of optical and thermal surveys for the different coastal sites and phenomena in study. UAV-derived optical imagery and thermal stream were processed by a Structure-from-Motion algorithm to create digital surface models (DSMs) and ortho-imagery for several key sites. UAV imagery were used as additional sources of detailed spatial data under large-scale mapping of current land-use and point sources of water pollution in the coastal zone, and a main data source on environmental violations, especially sewage discharge or illegal landfills. The revealed present-day coastal types were mapped at a large scale, and the net changes of shoreline position and rates of shore erosion were calculated on multi-temporal UAV data using modified Hausdorff’s distance. Based on highly-detailed DSMs, we revealed the areas and objects at risk of flooding under the projected water level rise to 1903.5 m along the west coasts of Minor Sevan being the most popular recreational area. We indicated that the structural and environmental state of marsh coasts and coastal wetlands as potential sources of lake eutrophication and associated algal blooms could be more efficiently studied under thermal UAV surveys than optical ones. We proposed to consider UAV surveys as a necessary intermediary between ground data and satellite imagery with different spatial resolutions for the complex environmental monitoring of the coastal area and water body of Lake Sevan as a whole.

Shoreline changes are important indicators of natural and manmade impacts on inland waters and particularly lakes. Man-induced changes in Lake Sevan water level during the 20th century affected not only the ecological status of the Sevan water but also near-shore areas. This article considers a long-term study of changes in Lake Sevan shoreline that occurred between 1973 and 2015. The Normalized Difference Water Index (NDWI) was applied to delineate the Sevan shoreline changes according to periods of lake water fluctuation from multi-temporal Landsat images and Historical changes in shorelines were analyzed with help of the Digital Shoreline Analysis System (DSAS) toolbox. Data obtained from the analysis have indicated that changes in the lake shoreline that occurred in different periods are similar to those in the lake water balance. Areas with the greatest shoreline changes have comparatively flat relief, so in the result of the lake water level raise vast forested areas were submerged. This study shows that application of multi-temporal spatial imagery and GIS methods can provide valuable information on time-and-space changes in the Sevan shoreline. Such information is important for monitoring Lake Sevan shoreline and nearshore changes.

High-mountainous Lake Sevan (Republic of Armenia) laying at an altitude of about 1900 m above sea level is a unique object of remote environmental monitoring due to the multidirectional dynamics of water level over the past 100 years. The artificial decrease in the lake water level began in 1930s, with the most intensive fall (over 10 m) from 1949 to 1962. In the 1990s, there was a slight increase in the level, then water level continued to fall until 2001. According to the current program of Armenian government, the lake level is planned to rise by at least 6 m in the coming years.The current increase in water level of Lake Sevan leads to activation of both abrasive and accumulative coastal processes, intensification of eutrophication and mass flowering of lake waters. Planned increase in water level also threats residential and recreational facilities which are abundant along shoreline of Lake Sevan. At the same time, the spatial and temporal differentiation between the current intensity of coastal processes and the state of coastal ecosystems is quite significant. In order to reveal the regularities of this differentiation, we preliminary carried out a retrospective large-scale mapping of the shoreline dynamics of Lake Sevan using archival and modern cartographic small-scaled materials and high-detailed remote sensing data for the period of over 100 years. Based on the results of interpretation of the mosaic of large-scale aerial imagery of 1960s different types of coasts were identified; the speed of receding of the lake shoreline during the period of its maximum decline was reconstructed.For several chosen key coastal areas, characterized by the most significant changes in shoreline and different types of current coastal processes, since 2018 we have been conducting operational remote monitoring of the coastal zone from light-weight UAVs DJI Phantom 4 Pro. UAV surveys are conducted at the low altitude range (100–200 m) with the use of both optical and thermal cameras. Resulted multitemporal UAV data are dense photogrammetric point clouds (with the density more than 300 points per sq. m), three-dimensional digital surface and terrain models with spatial and vertical resolution up to 10 cm, ultrahigh-detailed orthoimagery with the spatial extent about 1 sq. km. Thematic interpretation of acquired UAV data resulted to detailed land cover mapping of key coastal areas, reliable detection of local sources of water pollution, identification of buildings and facilities more threatened to inundation under the different scenarios of water level rising. The integral synthetic assessment is made for the current environmental state of coastal ecosystems under risk. Among more vulnerable ecosystems are coastal lagoons with associated wetland complexes and planted coastal forests which being degraded and damaged as a result of increase in lake level and inadequate management can substantially contribute to the deterioration of integral water quality in Lake Sevan.The study is supported by the RFBR project no. 18-55-05015-Arm_a. 

Comparative analysis of Russian network resources related to the strictly protected natural areas (ООPТ in Russian) is presented. Examples of geoportals, including inventory and multi-purpose, and of various territorial coverage are given

Geoinformatics as one of the information technologies that ensures the circulation of spatial data has long been ready for the further migration of its products and services to the digital environment. A detailed analysis of the Action Plan for the Information Infrastructure Program of the Digital Economy of the Russian Federation Program in the part related to section 04.03.016 “To create domestic digital platforms for the capturing, processing and dissemination of spatial data and remote sensing satellite data that meet the needs of citizens, business and government”, the de facto spatial data infrastructure (SDI), is given. The Plan of Activities also provides for the creation of the Common (Unified) Electronic Base Map (ersatz of fundamental spatial datasets), the federal spatial data portal (geoportal in international terminology), and the implementation of the “Digital Earth” from space project. The scientific GIS community, including the academic, will not remain aloof from the solution of the set tasks, in turn expecting from full-scale implementation of SDI of the Russian Federation better digital spatial data and simplification of access to them.