lowlands in the Georgian SSR, in western Transcaucasia between the Black Sea coast to the west, the Greater Caucasus to the northeast, and the Lesser Caucasus to the south. The lowlands stretch along the sea between the cities of Sukhumi and Kobuleti. In the west, they barely rise above sea level, and along the foothills of the mountains they are bordered by broken terraces up to 100–150 m high.
The Colchis lowlands are an alluvial plain occupying a depression of synclinal structure; the thickness of the Anthropogenic alluvium is up to 700 m. There are oil and gas shows, as well as mineral springs (Tskhaltubo). In the west, the surface of the lowlands has old riverbeds, channel banks, and low sandy hills, or lido. There are extensive swampy areas. The climate is subtropical and humid, with a mild winter, slight temperature fluctuations, abundant precipitation throughout the year (averaging 1,500 mm), and high air humidity. The mean January temperature is 4.5°–6.0°C; the mean August temperature, 23°–24°C
The Colchis lowlands are crossed by the Rioni, Inguri, and other rivers, which are given to flooding. Lake Paleostomi is by the sea near the city of Poti. In the west there is a predominance of swamp landscapes, with sedge-rush and sedge-motley grass vegetation, a sphagnum cover, and reed thickets. In the swamps a significant area is occupied by alder forests. Oak, beech, and beech-hornbeam forests with evergreen brush and lianas are found in the higher border areas. During the years of Soviet power, extensive work has been done to drain the swamps. Previously completely forested, the Colchis lowlands are largely planted with cereals (chiefly corn), orchards, and plantations of subtropical crops.
N. A. GVOZDETSKII