TY - GEN A1 - Chaves, Joaquín E. A1 - Neill, Christopher A1 - Germer, Sonja A1 - Neto, Sergio Gouveia A1 - Krusche, Alex V. A1 - Bonilla, Adriana Castellanos A1 - Elsenbeer, Helmut T1 - Nitrogen transformations in flowpaths leading from soils to streams in Amazon forest and pasture Y1 - 2009 UR - http://www.springerlink.com/content/101552 U6 - https://doi.org/10.1007/s10021-009-9270-4 SN - 1432-9840 ER - TY - JOUR A1 - Germer, Sonja A1 - Neill, Christopher A1 - Vetter, Tobias A1 - Chaves, Joaquín E. A1 - Krusche, Alex V. A1 - Elsenbeer, Helmut T1 - Implications of long-term land-use change for the hydrology and solute budgets of small catchments in Amazonia N2 - The replacement of undisturbed tropical forest with cattle pasture has the potential to greatly modify the hydrology of small watersheds and the fluxes of solutes. We examined the fluxes of water, Cl-, NO3--N: SO42---S, NH4+-N, Na+, K+, Mg2+ and Ca2+ in different flow paths in similar to 1 ha catchments of undisturbed open tropical rainforest and a 20 year-old pasture established from forest in the southwestern Brazilian Amazon state of Rondonia. Storm flow discharge was 18% of incident rainfall in pasture, but only 1% in forest. Quickflow predominated over baseflow in both catchments and in both wet and dry seasons. In the pasture, groundwater and quickflow were important flow paths for the export of all solutes. In the forest, quickflow was important for NO3--N export, but all other solutes were exported primarily by groundwater outflow. Both catchments were sinks for SO42--S and Ca2+, and sources of Na+. The pasture catchment also lost K+ and Mg2+ because of higher overland flow frequency and volume and to cattle excrement. These results show that forest clearing dramatically influences small watershed hydrology by increasing quickflow and water export to streams. They also indicate that tropical forest watersheds are highly conservative for most solutes but that pastures continue to lose important cations even decades after deforestation and pasture establishment. Y1 - 2009 UR - http://www.sciencedirect.com/science/journal/00221694 U6 - https://doi.org/10.1016/j.jhydrol.2008.11.013 SN - 0022-1694 ER -