Wilcke, W.; Leimer, S.; Peters, T.; Emck, P.; Rollenbeck, R.; Trachte, K.; Valarezo, C. & Bendix, J. (2013): <b>The nitrogen cycle of tropical montane forest in Ecuador turns inorganic under environmental change</b>. <i>Global Biogeochemical Cycles</i> <b>27</b>(4), 1194-1204.
Resource Description
Title:
The nitrogen cycle of tropical montane forest in Ecuador turns inorganic under environmental change
FOR816dw ID:
1255
Publication Date:
2013-12-03
License and Usage Rights:
FOR816 data user agreement: www.tropicalmountainforest.org/dataagreement.do
Resource Owner(s):
Individual:
Wolfgang Wilcke
Contact:
email:
wolfgang.wilcke <at> kit.edu
Karlsruhe Institute of Technology
Institute of Geography and Geoecology
Reinhard-Baumeister-Platz 1
76131 Karlsruhe
Baden-Württemberg
Germany
email:
rollenbe <at> staff.uni-marburg.de
Laboratory for Climatology and Remote Sensing
Faculty of Geography
Philipps University of Marburg
Deutschhausstr. 10
35032 Marburg
Germany
Individual:
Katja Trachte
Contact:
email:
katja.trachte <at> b-tu.de
Atmospheric Processes
Burger Chaussee 2
Campus Nord, LG 4/3
Brandenburg University of Technology Cottbus-Senftenberg
03044 Cottbus
Germany
email:
bendix <at> staff.uni-marburg.de
Faculty of Geography
Deutschhausstraße 10
Philipps University of Marburg
Laboratory for Climatology and Remote Sensing
35032 Marburg
Germany
Abstract:
Water-bound nitrogen (N) cycling in temperate terrestrial ecosystems of the Northern<br/>
Hemisphere is today mainly inorganic because of anthropogenic release of reactive N to<br/>
the environment. In little-industrialized and remote areas, in contrast, a larger part of<br/>
N cycling occurs as dissolved organic N (DON). In a north Andean tropical montane forest<br/>
in Ecuador, the N cycle changed markedly during 1998–2010 along with increasing<br/>
N deposition and reduced soil moisture. The DON concentrations and the fractional<br/>
contribution of DON to total N significantly decreased in rainfall, throughfall, and soil<br/>
solutions. This inorganic turn of the N cycle was most pronounced in rainfall and became<br/>
weaker along the flow path of water through the system until it disappeared in stream water.<br/>
Decreasing organic contributions to N cycling were caused not only by increasing inorganic<br/>
N input but also by reduced DON production and/or enhanced DON decomposition.<br/>
Accelerated DON decomposition might be attributable to less waterlogging and higher<br/>
nutrient availability. Significantly increasing NO3-N concentrations and NO3-N/NH4-N<br/>
concentration ratios in throughfall and litter leachate below the thick organic layers indicated<br/>
increasing nitrification. In mineral soil solutions, in contrast, NH4-N concentrations increased and NO3-N/NH4-N concentration ratios decreased significantly, suggesting increasing net ammonification. Our results demonstrate that the remote tropical montane forests on the rim of the Amazon basin experienced a pronounced change of the N cycle in only one decade. This change likely parallels a similar change which followed industrialization in the temperate zone of the Northern Hemisphere more than a century ago.
Keywords:
| climate change | nitrification | N deposition | terrestrial N cycling | dissolved organic N |
Literature type specific fields:
ARTICLE
Journal:
Global Biogeochemical Cycles
Volume:
27
Issue:
4
Page Range:
1194-1204
Publisher:
Wiley
Publication Place:
Hoboken, NJ, USA
ISSN:
1944-9224
Metadata Provider:
Individual:
Wolfgang Wilcke
Contact:
email:
wolfgang.wilcke <at> kit.edu
Karlsruhe Institute of Technology
Institute of Geography and Geoecology
Reinhard-Baumeister-Platz 1
76131 Karlsruhe
Baden-Württemberg
Germany