Abstract

In an empirical/statistical approach, the relationship between watershed characteristics and the inter-lake variance of chemical lake water composition is analyzed. The lake water quality data sampled in 87 extensively monitored glacial/boreal lakes is hence supplemented with digital landscape information covering the categories: geology, soils, land cover, and topography. With standard I : 50 000 scale maps as the source of information, 33 classes of landscape elements are identified and described with respect to morphological and hydrological characteristics. When regression models based on the combined morphology/ hydrology information are compared with models excluding the hydrology information, the hypothesis whether or not information regarding hydrological watershed characteristics improves the performance of existing models can be tested. It is concluded that the introduction of hydrological element descriptors significantly improves the overall performance of regression models describing the inter-lake variance of lake water: hardness, color, pH, total phosphorus concentration, alkalinity, conductivity, and Secchi depth. When these variables are ranked according to the amount of model performance achieved, the general importance of surface hydrology in the process of emitting and transporting associated substances through the landscape can be assessed. Out of the 33 landscape elements totally digitized, ten are identified as significantly correlated to the inter-lake variance of characterizing lake water quality. When they are ranked according to their influential power, the consequence of watershed interference can be qualitatively assessed. The results should be easily implemented in watershed management and because of the general validity given by the extensive empirical database - valid in many glacial/boreal watersheds throughout the world. (C) 1999 Elsevier Science B.V. All rights reserved.

Keywords

Catchment hydrology; lake water quality; statistical modeling

Published in

Journal of Hydrology
1999, Volume: 216, number: 1-2, pages: 1-16
Publisher: ELSEVIER SCIENCE BV

Associated SLU-program

Lakes and watercourses


UKÄ Subject classification

Oceanography, Hydrology, Water Resources


Publication identifier

DOI: https://doi.org/10.1016/S0022-1694(98)00244-3

Permanent link to this page (URI)

https://res.slu.se/id/publ/44183