Environmental factors affecting paludification
The three partial models based on environmental
variable groups for lake level paludification are presented
in Table 5. At the lake level two catchment
characteristic variables explained 49% of the variation
(explained deviance 173.5 out of the total deviance
352.9) in paludification. The cover of clay soil had a
positive response, and altitude of the lake a negative
response to paludification. Total phosphorus (positive
response) was the only variable included in the lake level
water quality model explaining 45% of the variation in
paludification. Two water level regulation variables
explained 44% of the variation: the extent of spring
flooding had a general negative response to paludification
with only a slight tendency to level off towards the
largest values of the variable (second-order polynomial
term), whereas regulation as a binary variable had a
positive response to paludification. The three partial
models for site level littoral paludification are presented
in Table 6. Only one site morphology variable was
selected for the model, namely slope angle. It had a
negative response to paludification, explaining 8% of
the variation. Soil variables explained 11% of the
variation of the site level paludification; rock and sand
had a negative and clay a positive response to
paludification. Vegetation variables explained 15% of
the site level paludification; reed sweet-grass, nymphaeids
and eutrophy indicator variables were included
in the aquatic vegetation model with a positive response
to paludification.