Why is biodiversity so high in temperate deciduous forests and so low in desert or tundras?

Temperature deciduous forests occur in mid-latitudes (Figure 4) where cool winters, warm summers, and high year round precipitation occurs (Figure 9). ... Biodiversity is relatively high in this biome due to the niche partitioning allowed by the multiple forest layers.

The deserts and arctic tundra support much smaller biomass of animals than tropical forest because it has smaller vegetation. Tropical forest has a broad range of plants and vegetation causing more animals. ... It can also be protection from other animals.

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