Environmental filtering controls soil biodiversity in wet tropical ecosystems

The environmental factors controlling soil biodiversity along resource gradients remain poorly understood in wet tropical ecosystems. Aboveground is expected to be driven by changes nutrient availability these ecosystems, however, much less known about the importance of driving biodiversity. Here, we combined a cross-continental survey across regions with three decades' field experiment adding nitrogen (N) and phosphorus (P) (100 kg N ha−1y−1 100 P ha−1y−1) Hawai'ian forests contrasting substrate ages (300 4,100,000 years) investigate influence explain bacteria, fungi, protists, invertebrates key functional genes. We found that was acidification during long-term pedogenesis gradients, rather than limitations. In fact, our results showed experimental additions caused substantial soils from Hawai'i. These declines pH were related large decreases ecosystems four continents. Moreover, microbial activity did not change response additions. concluded filtering drives multiple organisms, effects associated can further create undesired net negative on overall naturally acid soils. This knowledge integral for understanding management globally.