Black Sea–Caspian Steppe The Manych Depression is not much more than 65 feet above sea level and the area around Astrakhan and part of Kalmykia is below sea level. Rivers: Through the center runs the northwest-tending Kuma-Manych Depression. This was once a strait connecting the Black and Caspian Seas and is now marked by the Manych River which is basically a chain of lakes. It will probably be the route of the Eurasia Canal if that great engineering work is ever built. In the south the rivers that flow north from the Caucasus are caught by the west-flowing Kuban River and the east-flowing
Black Sea reports of flares on the Black Sea occurring during thunderstorms, possibly caused by lightning igniting combustible gas seeping up from the sea depths. The Black Sea supports an active and dynamic marine ecosystem, dominated by species suited to the brackish, nutrient-rich, conditions. As with all marine food webs, the Black Sea features a range of trophic groups, with autotrophic algae, including diatoms and dinoflagellates, acting as primary producers. The fluvial systems draining Eurasia and central Europe introduce large volumes of sediment and dissolved nutrients into the Black Sea, but distribution of these nutrients is controlled by the degree of physiochemical