Why are nutrient-poor soils especially important to the fynbos of South Africa?

Nutrient-poor soils are a defining feature of the fynbos biome in South Africa, and they play a critical role in fostering its extraordinary plant diversity.12

In scrubland ecosystems that have existed for long periods, such as the fynbos, these challenging soil conditions are directly linked to high levels of floristic richness. The nutrient-poor, acidic soil environment acts as a selective pressure that has allowed for the evolution of a vast array of specialized species. This unique ecological niche supports more than 8,500 plant species, a large proportion of which are endemic—meaning they are found nowhere else on Earth.213

By limiting the dominance of a few fast-growing species, these nutrient-poor conditions help maintain the complex, diverse community structure characteristic of the fynbos, where many small herbaceous plants thrive beneath a canopy of specialized shrubs.32