Bücker, A.; Crespo, P.; Frede, H.; Vaché, K.; Cisneros, F. & Breuer, L. (2010): <b>Identifying Controls on Water Chemistry of Tropical Cloud Forest Catchments: Combining Descriptive Approaches and Multivariate Analysis</b>. <i>Aquatic Geochemistry</i> <b>16</b>(1), 127-149.
Resource Description
Title:
Identifying Controls on Water Chemistry of Tropical Cloud Forest Catchments: Combining Descriptive Approaches and Multivariate Analysis
email:
hans-georg.frede <at> umwelt.uni-giessen.de
Heinrich-Buff-Ring 26
Institute for Landscape Ecology and Resources Management
Justus-Liebig-University Gießen
35392 Gießen
Germany
Individual:
Kellie Vaché
Contact:
email:
vachek <at> engr.orst.edu
Justus-Liebig-University Gießen
Institute for Landscape Ecology and Resources Management
Heinrich-Buff-Ring 26
35392 Gießen
Germany
Individual:
Felipe Cisneros
Contact:
email:
webmaster <at> tropicalmountainforest.com
Individual:
Lutz Breuer
Contact:
email:
lutz.breuer <at> umwelt.uni-giessen.de
Heinrich-Buff-Ring 26
Institute for Landscape Ecology and Resources Management
Justus-Liebig-University Gießen
35392 Gießen
Germany
Abstract:
Abstract We investigated controls on the water chemistry of a South Ecuadorian cloud<br/>
forest catchment which is partly pristine, and partly converted to extensive pasture. From<br/>
April 2007 to May 2008 water samples were taken weekly to biweekly at nine different<br/>
subcatchments, and were screened for differences in electric conductivity, pH, anion, as<br/>
well as element composition. A principal component analysis was conducted to reduce<br/>
dimensionality of the data set and define major factors explaining variation in the data.<br/>
Three main factors were isolated by a subset of 10 elements (Ca2?, Ce, Gd, K?, Mg2?,<br/>
Na?, Nd, Rb, Sr, Y), explaining around 90% of the data variation. Land-use was the major<br/>
factor controlling and changing water chemistry of the subcatchments. A second factor was<br/>
associated with the concentration of rare earth elements in water, presumably highlighting<br/>
other anthropogenic influences such as gravel excavation or road construction. Around<br/>
12% of the variation was explained by the third component, which was defined by the<br/>
occurrence of Rb and K and represents the influence of vegetation dynamics on element<br/>
accumulation and wash-out. Comparison of base- and fast flow concentrations led to the<br/>
assumption that a significant portion of soil water from around 30 cm depth contributes to<br/>
storm flow, as revealed by increased rare earth element concentrations in fast flow samples.<br/>
Our findings demonstrate the utility of multi-tracer principal component analysis to study<br/>
tropical headwater streams, and emphasize the need for effective land management in<br/>
cloud forest catchments.
Additional Infos:
This is online first, the printed version is not available yet
Keywords:
| Ecuador | water quality | land-use change | rare earth elements | principal component analysis | tropical cloud forest |
