Limitations to the growth of epiphytes and the productivity of associated methanogens in neotropical moist forests

• Applicant: Dr. Florian Werner
• Subject Area: Ecology and Biodiversity of Plants and Ecosystems
• Term: from 2007 to 2014
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 29937865

Epiphytes play an important role in tropical forest ecosystem processes by influencing fluxes of water, carbon and nutrients. Tank bromeliads, a common group of epiphytes, also affect atmospheric CH4 budgets by hosting active communities of methanogens. At present, the limitations to epiphyte growth and the productivity of associated methanogens are poorly understood. The proposed study addresses two main questions: (1) To what extent are establishment and growth of epiphytes in undisturbed montane forest limited by nutrient availability? Epiphyte growth response to fertilisation with moderate doses of N, P, and NP will be monitored in late juveniles of selected vascular species from different functional and taxonomical groups. Additionally, epiphyte propagules (angiosperms, foliose lichens) will be sown experimentally to determine fertilisation effects on early establishment rates and seedling growth. (2) How do per capita and ecosystem-level CH4 emissions from bromeliad tanks change with elevation, and which factors limit the productivity of bromeliad methanogens? Data on per capita CH4 emissions and bromeliad densities will be taken along an elevational gradient of 250–3000 m asl. Furthermore, limitations to methanogens (water, carbon, nutrients, temperature) will be explored through in situ greenhouse experiments.

• DFG Programme: Research Units
• Subproject of: FOR 816: Biodiversity and Sustainable Management of a Megadiverse Mountain Ecosystem in Southern Ecuador
• International Connection: Ecuador
• Participating Person: Zhofre Aguirre