Tropical montane cloud forests (TMCF) are high-elevation forests characterized by persistent low-level cloud cover. Cloud forests are biodiversity hotspots due largely to the increased precipitation that occurs as mist from cloud immersion. Unfortunately, the cloud layer is rising due to global warming, leading to drier and warmer conditions. We use an elevation gradient in a TMCF representing natural shifts in temperature and moisture to mimic climate change and assess the effects on fungal communities. We conducted a soil translocation experiment along an elevation gradient within the Monteverde Cloud Forest Reserve (10º18´N, 84º47´W) in Monteverde, Costa Rica. Soil was reciprocally translocated to higher and lower elevations in order to determine how fungal communities respond. Soil cores were placed in nylon membrane bags that prevent colonization of local fungi into these cores, but allow the passage of water, nutrients, and organic compounds. Soils were collected after 5 and 10 months after the wet and dry seasons respectively. Fungal diversity was measured using high-throughput sequencing and a primer set targeting the fungal ITS region to determine how fungi respond to different temperature and moisture regimes.
Results/Conclusions
Fungal communities shifted significantly after experiencing 5 months of 0, 1, 2, 3, 4, and 5°C warmer temperature associated with lower elevations (p < 0.011). Moreover, fungal communities shifted significantly after experiencing 10 months of 0, 1, 2, 3, 4, and 5°C cooler temperature associated with higher elevations (p < 0.032). These changes in fungal community composition may coincide with shifts in important fungal functional groups. We are currently delving deeper into the community to examine this possibility. Climate change is exposing this TMCF to drier and warmer conditions. This elevation gradient is an important tool in understanding responses of soil fungi to climate change in their natural environment. Overall, this research will provide better predictions for how fungal communities may be altered due to climate change.