Vol 156, No 1 (2024)

For the past few years, the Institute of Limnology of the Russian Academy of Sciences has been conducting geological and geomorphological studies of the bottom of Lake Ladoga. Starting from 2018, underwater photo and video cameras developed at the Institute began to be used in these studies. The use of this new research tool led to the discovery of a number of new facts about the structure of the bottom of Lake Ladoga. In particular, at the bottom of the northern part of Lake Ladoga, three subvertical ledges were found, composed of bedrock, up to 70–100 meters high. According to a number of features, such as the bedrock composition of rocks, morphology and spatial correspondence to known fault zones, these ledges can be recognized as morphological expressions of tectonic objects – faults of presumably fault type. The absence of visible traces of glacial processing on the bedrock blocks suggests the Holocene age of the formation of these ledges and, accordingly, the existence of modern active tectonic movements in the area of Lake Ladoga.

The results of studies of soil flushing and accumulation in the period 2009–2017 in the northern part of the Krasnoyarsk forest-steppe in areas with high intensity of erosive and accumulative processes are presented. A wide range of erosion values from meltwater has been established – from 0.4 to 25 mm for the spring period. The results of the application of a refined Regional model for calculating potential flushing for the northern part of the Krasnoyarsk forest-steppe are presented. The analysis of meteorological factors and conditions of the underlying surface affecting the distribution of values of melt runoff, flushing and accumulation of soils on arable massifs located on inclined watershed surfaces is carried out: the specificity of the distribution of meltwater flows determines the formation of zones of extreme erosion along the perimeter of arable land in the lower parts of the slope – up to 15–20 mm of soil layer. In conditions of low slope steepness, the effect of relief on erosion is largely determined by the high slope lengths and melt water flow lines. The distribution of flushing values over the area of arable land shows a close correlation with the values of snow accumulation and soil moisture. The spatial and temporal patterns of the influence of the previous autumn soil moisture on the intensity of erosion have been established: the values of flushing increase with increasing soil moisture, the average values of erosion correlate with the values of autumn soil moisture in dynamics over the years of field observations. Special soil protection measures have been proposed for sites with the most intensive flushing in the research area.

The problems of negative ecological changes of Vorobyovy Gory Nature Reserve associated with visual pollution of its territory, which simultaneously performs environmental and recreational functions, were considered. In particular, two of its aspects were distinguished: information and light pollution. Their implications for the environment and humans were analyzed. The methods of quantitative assessment of these implications were given, the issues of objectivity of information pollution assessments were discussed. Based on instrumental measurements of light pollution, a map of its distribution on the territory of the nature reserve was made. The risks of visual pollution of this territory associated with the loss of its natural and cultural heritage were indicated. Ways of regulating visual pollution were proposed.