The soil fauna of a tropical montane rain forest
- Soil fauna of tropical forests What is the relative strength of the regulative forces controlling decomposition processes and the food web of the decomposer fauna?
- Phylogeography of representative tropical soil animal species
Compared to temperate and boreal forest ecosystems the density of soil animals in tropical mountain forests is low. Commonly, the low density of decomposer invertebrates in tropical forests is ascribed to the fast turnover of litter material and low availability of soil organic matter as food. This explanation, however, does not fit for the patterns found at the Ecuadorian study side.
In this project we therefore want to disentangle the relative strength of the regulative forces controlling decomposition processes and the food web of the decomposer fauna. Therefore we are manipulating biotic and abiotic conditions (temperature, altitude, humidity and food resource) in field and laboratory experiments. We focus on Testacea and microarthropods (especially Oribatida) as representatives of bacterial and fungal feeders in the decomposer system.
What is the genetic relationship between temperate and tropical soil animal species?
In both of our focal animal groups, Testacea and Oribatida, the species of the studied mountain rain forest in part overlap with species from temperate forest ecosystems. This raises the question of the genetic relationship between the cosmopolitan species from temperate and tropical regions. Gene flow between sexual species of tropical and temperate regions is theoretically possible, whereas parthenogenetic species from temperate and tropical regions likely are genetically distinct. Investigating the genetic variation of sexual and parthenogenetic species from temperate and tropical regions (e.g. Rostrocetes spp.) will reveal if those taxa are recently dispersed or have a Pangaean distribution since millions of years.