The ecosystems that receive the least amount of rainfall on average are the Tundra and the Desert.
1. Tundra: The Tundra is a cold, treeless biome found in the Arctic and Antarctic regions. It has a very dry climate with low precipitation levels, mostly in the form of snow. The cold temperatures in the Tundra limit the amount of moisture available, resulting in low rainfall.
2. Desert: Deserts are known for their arid conditions and minimal rainfall. They receive very little precipitation throughout the year, leading to dry and hot environments. Deserts like the Sahara in Africa or the Mojave in the United States are examples of ecosystems with low rainfall.
Therefore, when comparing the options provided, the Tundra and Desert ecosystems are the ones that receive the least amount of rainfall on average.
