The influence of leaf litter diversity and soil fauna on initial soil erosion in subtropical forests
Created at: 2013-10-17
Initial title: How does litter cover, litter diversity and fauna affect sediment discharge and runoff?
Envisaged journal: Earth surface processes and landforms (ESPL)
Envisaged date: 2015-01-26
Soil erosion is one of the main environmental problems, especially in subtropical regions with monsoon climate. Afforestation is suggested to be an ecological solution for the loss of soil. Litter cover plays a major role in soil erosion processes. It is known that litter cover reduces erosivity of raindrops, decreases sediment discharge and lowers runoff volume compared to bare ground. Litter cover is influenced by the diversity of tree species and species-specific relationships as well as decomposers which transform the litter to humus. Decomposers such as representatives of meso- and macrofauna can show both negative and positive effects on soil erosion. Focusing on initial soil erosion (splash), our experimental setup is designated to get a better understanding of these mechanisms.
In a fully factorial design NILEx determined the effect of both litter diversity and meso- and macrofauna on the extent of soil erosion. 96 runoff plots (40cm x 40cm) on two hill slopes inside a castanea molissima plantation have been installed and filled with seven different leaf species. 16 one-species plots, 24 two-species plots, 4 four-species plots and 4 bare ground plots have been set up, each replicated once. We prepared 48 plots with pitfall traps (Renner solution) for soil meso- and macrofauna (e.g. diplopods and collembola), so half of the plots were kept free from fauna while the other half was accessible. Rainfall was generated by a rainfall simulator with a continuous and stable intensity of 60 mm/h. Our experiments included two runs of 20 minutes duration each, both conducted at two different time steps (summer 2012 and autumn 2012). Litter coverage and litter mass were recorded at the beginning and at the end of the experiment.