Trace gas fluxes from tropical montane forests of Southern Ecuador Methane (CH4) nitrous oxide (N2O) and carbon dioxide (CO2) are major greenhouse gases but their fluxes in tropical montane forests are hardly known. The distribution of known sources of CH4 (e.g. soil wetlands) fail to explain high CH4 concentrations above tropical montane forest canopies that were observed by space borne measurements. Additionally there are indications in recent literature that responses of soil N2O and CO2 fluxes to projected increases in nitrogen (N) deposition in tropical forest areas can be predicted from nutrient limitation of vegetation growth. However nutrient controls on N and C cycling processes have rarely been studied in tropical montane forests. This dissertation tries to elucidate (1) the role of tank bromeliads growing in canopy wetlands of neotropical montane forests as a potential source of CH4 that may help to explain the high CH4 concentrations above neotropical forest canopies (2) nutrient controls on rates of soil N cycling and soil N2O fluxes and (3) nutrient controls on soil respiration in Andean neotropical montane forests of Southern Ecuador ...