TY  - JOUR
A1  - Hoffmann, Bernd
A1  - Feakins, Sarah J.
A1  - Bookhagen, Bodo
A1  - Olen, Stephanie M.
A1  - Adhikari, Danda P.
A1  - Mainali, Janardan
A1  - Sachse, Dirk
T1  - Climatic and geomorphic drivers of plant organic matter transport in the Arun River, E Nepal
JF  - Earth & planetary science letters
KW  - plant wax biomarker
KW  - leaf wax delta D
KW  - carbon cycle
KW  - remote sensing
KW  - erosion
Y1  - 2016
U6  - https://doi.org/10.1016/j.epsl.2016.07.008
SN  - 0012-821X
SN  - 1385-013X
VL  - 452
SP  - 104
EP  - 114
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Olen, Stephanie M.
A1  - Bookhagen, Bodo
A1  - Hoffmann, Bernd
A1  - Sachse, Dirk
A1  - Adhikari, Danda P.
A1  - Strecker, Manfred
T1  - Understanding erosion rates in the Himalayan orogen: A case study from the Arun Valley
JF  - Journal of geophysical research : Earth surface
N2  - Understanding the rates and pattern of erosion is a key aspect of deciphering the impacts of climate and tectonics on landscape evolution. Denudation rates derived from terrestrial cosmogenic nuclides (TCNs) are commonly used to quantify erosion and bridge tectonic (Myr) and climatic (up to several kiloyears) time scales. However, how the processes of erosion in active orogens are ultimately reflected in Be-10 TCN samples remains a topic of discussion. We investigate this problem in the Arun Valley of eastern Nepal with 34 new Be-10-derived catchment-mean denudation rates. The Arun Valley is characterized by steep north-south gradients in topography and climate. Locally, denudation rates increase northward, from <0.2mmyr(-1) to similar to 1.5mmyr(-1) in tributary samples, while main stem samples appear to increase downstream from similar to 0.2mmyr(-1) at the border with Tibet to 0.91mmyr(-1) in the foreland. Denudation rates most strongly correlate with normalized channel steepness (R-2=0.67), which has been commonly interpreted to indicate tectonic activity. Significant downstream decrease of Be-10 concentration in the main stem Arun suggests that upstream sediment grains are fining to the point that they are operationally excluded from the processed sample. This results in Be-10 concentrations and denudation rates that do not uniformly represent the upstream catchment area. We observe strong impacts on Be-10 concentrations from local, nonfluvial geomorphic processes, such as glaciation and landsliding coinciding with areas of peak rainfall rates, pointing toward climatic modulation of predominantly tectonically driven denudation rates.
Y1  - 2015
U6  - https://doi.org/10.1002/2014JF003410
SN  - 2169-9003
SN  - 2169-9011
VL  - 120
IS  - 10
SP  - 2080
EP  - 2102
PB  - American Geophysical Union
CY  - Washington
ER  -