Based on the results of geomorphologic surveys carried out in 2021-2022 with the involvement of published materials, an original largescale (from 1:25 000 to 1:100 000) description of relief of urban areas of the Republic of Abkhazia (Gagra, Pitsunda, Gudauta, Noviy Afon and Sukhum) was compiled, and unprec-edented general geomorphologic maps were prepared, with morphogenesis-based legends. According to their morphostructure position and geomorphologic structure, the cities are grouped as follows: 1) completely lying in the area of the coastalmarine relief (Pitsunda and Gudauta); 2) located mainly within the sea terraces and erosion-denudation hills (Sukhum and Gagra); 3) completely located in the low mountains with a predominance of strongly dissected structural-denudation, fluvial and slope relief (Noviy Afon). A field survey revealed about 300 areas with unfavorable and dangerous geomorphologic processes within the urban areas, 44% of them are in Sukhum, 26% in Gudauta, 11% in Gagra, 10% in Pitsunda, 9% in Noviy Afon. The leading geo-morphologic hazards in all spectra are suffusion, erosion and biogenic processes. A list of other processes in a spectrum is predetermined by the geomorphologic position of cities. The widest range, which in addition to the abovementioned processes, includes also karst, mudflows and landslide processes (i.e. the most dangerous ones), is typical for urban areas with a complex relief structure, abundant in steep slopes and located within a narrow strip separating the spurs of the Main Caucasian Range from the sea (Gagra, Noviy Afon). The risk of destruction of street infrastructure (roadbed, communications, etc.) by dangerous geomorphologic processes was qualitatively estimated and its high dependence on the geomorphologic position of a particular section of the city has been established. In particular, the distribution patterns of recorded unfavorable and dangerous geomorphologic processes made it possible to state that the most favorable conditions for the construction and operation of urban infrastructure and buildings in general are within the leveled surfaces of the Late Pleistocene marine terraces, as well as the upper levels of floodplain terraces in the valleys of large rivers. Other levels of relief have certain disadvantages that impede the development of territories. Thus, the construction on the surface of the Holocene marine terrace is possible only if the foundations are waterproofed and soil is dumped in the lower areas. The development of high sea terraces, erosion-denudation and structural-denudation relief is difficult because of the high density of erosion dissection.

1Ъе paper f(x;uses on environmental considerations associated with the development of new infrastructure for the 2014 Winter Olympic Games in the Sochi Region of Southern Russia. Environmental threats associated with new infrastructure may result in more powerful geomorphological processes occurring between the Caucasus Mountains and the Black Sea. This region features steep slopes, flixxiplains of mountain rivers, landslides and a seashore. The Sochi Region experiences strong geomorphological processes, which often reach catastrophic proportions. Some causes include powerful earthquakes, little resistance on the part of the flysch parent material as well as precipitation of up to 2,000 mm per year occurring primarily during the winter season. The environmental conditions in the region favor high rates of physical and chemical weathering, which results in the formation of a thick weathering cover originating on slopes. In effect, 85% of slope areas arc affected by landslides. This strongly suggests that exogenic processes need to be monitored in the Sochi Region in order to protect urban and rural communities as well as roads, bridges and other transportation infrastructure. Research in 2005-2007 focused on the rate of bcdrock weathering, rate of slope cover movement, rill and gully erosion, stream channel processes, suffosion and landslides. This paper provides initial results from this research. The Sochi Region is the largest Russian recreational area. Visitor population during the peak of a summer season in some years twice exceeds the native population (about 400 thousand people). The territory is densely built-up. Besides the general infrastructure there arc hundreds o f objects for recreational service. Especially rapid growth of construction activity is taking place nowadays in connection with the W inter Olympic Games that will be held in the Sochi Region in 2014. Most of the settlements in the Sochi Region are concentrated in a narrow zone bounded by the sea coast and mountain ranges. Smaller towns and villages merge into united large urbanized area stretched along the Black Sea coast. The most convenient areas for building such as coastal plains, river terraces and Hat hilltops have been com pletely settled quite long ago. Active house-building and recreation expansion leads to the use of steep slopes, floodplains of mountain rivers and seashore for construction. Sochi is a region rich in natural heritage. There are a lot o f beautiful mountain valleys, cliffs, caves, waterfalls, ctc. Vast number of tourists and developed excursion service cause a strong pressure Mass movement rales, mm/year 1,0 2,0 3,0 4,0 on these natural objects Thus there is a high anthropogenic and recreational load on the whole area. Besides. The Sochi Region has some special natural features favourable for the development of cxogcnic geomorphic processes including catastrophic ones. Those include mountainous relief, high topography range and dom inance o f steep slopes. The area is a part of earthquakes zone with magnitude 8-9. Geological structure of the region is dominated by flysch. Alternating siltstone, mudstone, marl and sandstones are mostly prone to weathering and erosion. Local clim ate is unique for Russian conditions and deserves special attention. Sochi is a subtropical region with high temperatures and precipitation (up to 2000 mm per year), mostly heavy rains and storms during winter season. Such environment produces favourable conditions for active physical and especially chemical weathering. As a consequence, relatively thick regolith covers all the surfaces. W eathering mantle in combination with water abundance, steep slopes and dominantly inclined bedding o f bedrocks favours the development of landslides, which occupy up to 85% of the area. A number of other slope processes, erosion, fluvial and coastal phenomena, karst are also widespread in the Sochi Region. Rates of these exogenic geom orphic processes are mostly few times higher then in other parts of Russia. From the above considerations it is evident that monitoring o f exogenic processes is important for the assessment of geomorphic hazards to safety of people, civil engineering, infrastructure and communications. During regular fieldworks in 2005-2007 we renewed and founded som e new monitoring stations to study weathering, creep, rill and gully erosion, channel processes, suffosion and landslides. This paper presents some results of this continuing work. The first process of our research is weathering. Six samples o f bedrock (mudstone, siltstone and sandstone two samples o f each) were taken. Weighed and photographed in the lab, they were wrapped in kapron bags permeable to the air, water and temperature fluctuation, but not allowing the material to leak out. Afterwards the samples in 2 groups of 3 ( I of each rock) were put: I s' group in the open air on soil surface; 2nd group to the depth o f 30 cm into the soil. Next weighting was implemented in a year. All the samples were reduced (tab. I ). The average reductions have been 8.5% for mudstone, 2.2% for siltstone and 14.8% for sandstone. Possibly the highest level of porosity and accordingly the largest specific area accessible to the environment are the most important factor of weathering rate and cause the heaviest decay of sandstones if com pare with the others. The rate of mudstone weathering is higher then of siltstone. This is probably related to the highest heat conductivity o f mudstone among the studied rocks. Thus size of grains making the rock does not have a strong influence on weathering rates. According to first results of this research porosity and heat conductivity are the most important factors of weathering in the environm ent of humid subtropics. Fig.l. Mass movement rates in soil sections upslope (a) and downslope (b).