The effects of drought on the leaf-litter invertebrates of an Australian Wet Tropics ecosystem: the Daintree Rainforest Effects of drought on tropical leaf-litter invertebrates

Abstract

Climate change is impacting ecosystems worldwide, and tropical rainforests, in particular, are extremely vulnerable. Tropical rainforests are predicted to experience drought events with increasing frequency, duration and severity. Understanding how drought will impact these ecosystems is critical to management strategies. In particular, understanding how drought will impact tropical leaf-litter invertebrates will provide insight into broader impacts across the entire ecosystem. We investigated the impacts of drought on leaf-litter invertebrate abundance and diversity in the Daintree Rainforest of Far North Queensland, Australia. Additionally, we investigated the ways in which litter depth, soil moisture and substrate type impact leaf-litter invertebrate abundance. We found that neither number of functional groups nor number of orders was different in drought-treated sites compared to control sites, but that invertebrate abundance was significantly lower in drought-treated sites. We found that neither soil moisture nor litter depth had any significant effect on leaf-litter invertebrate abundance or diversity. Substrate type did not affect the number of functional groups or orders present, but we found significantly higher leaf-litter invertebrate abundance in sites with rock substrate, compared to soil substrates.