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Presented at the NABS Annual meeting, Pittsburgh, Pennsylvania, 2002
in Periphyton
ASSESSING SPATIAL PATTERNS OF PERIPHYTON AND MOSS IN A SUBALPINE SPRING COMPLEX USING GPS AND GIS.
M. Doering, U. Uehlinger, and C.T. Robinson. Swiss Federal Institute for Environmental Science and Technology (EAWAG), Department of Limnology, Ueberlandstrasse 133, 8600 Duebendorf, Switzerland
We examined spatial patterns of periphyton and moss in a subalpine spring-complex (1960 m a.s.l.) in the Swiss National Park (wetted spring area = 910 m2, water volume = 92 m3). Methods included spot measurements of nutrients, periphyton and moss biomass (chlorophyll a, ash-free dry mass), potential light availability (fisheye photographs), sediment structure, and geodetic techniques (GPS) for the assessment of channel morphology and moss cover. GIS was used to evaluate the habitat template of periphyton and moss. This combination of methods allowed a rapid spatial survey at a high spatial resolution (<4 cm), particularly for subaqueous areas where the use of photogrammetric methods is restricted. Stepwise multiple regression analysis indicated that nutrients and substratum size were the most important predictors of periphyton biomass (R2= 0.67). Based on the regression analysis the potential spatial distribution of periphyton biomass within the channel network was modeled with GIS. However the spatial distribution of periphyton was constrained by dense moss stands that covered about 90% of the wetted channels. GPS revealed to be a useful tool for the meso-spatial assessment of moss and other morphological characteristics of the spring-complex providing accurate meso-scale mapping.
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