Give four reasons why most rift valley lakes are salty?

1. Limited inflow of fresh water: Rift valley lakes are often located in arid or semi-arid regions where there is limited rainfall and few rivers or streams feeding into the lakes. This results in a lack of fresh water input, leading to higher concentrations of salts in the water.

2. Evaporation: The high temperatures and strong sunlight in rift valley regions lead to high rates of evaporation. As water evaporates, the salts and minerals in the water become more concentrated, resulting in higher salinity levels in the lakes.

3. Geological factors: Rift valley lakes are often located in areas with high levels of volcanic activity and tectonic activity. This can result in the release of minerals and salts from the surrounding rocks and sediments, which can contribute to the salinity of the lakes.

4. Endorheic basins: Many rift valley lakes are located in endorheic basins, which are closed drainage basins that do not have an outlet to the sea. This means that any salts and minerals that are carried into the lake by rivers or streams are not able to be flushed out, leading to the accumulation of salts and increasing salinity levels in the lake over time.