Most animals find the lake's high temperature (up to 60 ☌ ) and its high and variable salt content inhospitable. The alkali salt crust on the surface of the lake is also often coloured red or pink by the salt-loving microorganisms that live there.Salt marshes and freshwater wetlands around the edges of the lake do support a variety of plants. The red accessory photosynthesizing pigment in the cyanobacteria produces the deep reds of the open water of the lake and the orange colours of the shallow parts of the lake. Such halophile organisms include some cyanobacteria that make their own food with photosynthesis as plants do. As water evaporates during the dry season, salinity levels increase to the point that salt-loving microorganisms begin to thrive. The colour of the lake is characteristic of those where very high evaporation rates occur. This has allowed the lake to concentrate into a caustic alkaline brine. The lavas have significant amounts of carbonate but very low calcium and magnesium levels. The surrounding bedrock is composed of alkaline, sodium-dominated trachyte lavas that were laid down during the Pleistocene period. The alkalinity of the lake can reach a pH of greater than 12.

High levels of evaporation have left behind natron (sodium carbonate decahydrate) and trona (sodium sesquicarbonate dihydrate). Temperatures at the lake are frequently above 40 ☌ (104 ☏). The surrounding area receives irregular seasonal rainfall, mainly between December and May totalling 800 millimetres (31 in) per year. The lake is a maximum of 57 kilometres (35 mi) long and 22 kilometres (14 mi) wide. It is quite shallow, less than three metres (9.8 ft) deep, and varies in width depending on its water level. The lake is fed principally by the Southern Ewaso Ng'iro River, which rises in central Kenya, and by mineral-rich hot springs. The lake is within the Lake Natron Basin, a Ramsar Site wetland of international significance. It is in the Gregory Rift, which is the eastern branch of the East African Rift. Lake Natron is a salt or alkaline lake located in north Ngorongoro District of Arusha Region in Tanzania.

Lago natron rio