Materials & Methods
A total of 48 clear-cuts (Table 1) were used in this study. Half of the clear-cuts had a history of meadow and the other half a history of forest. All clear-cuts varied in time since clear-cutting (TSC) between 2-8 years.
Butterflies and burnet moths were inventoried three times throughout the summer of 2013 using the Pollard Walk method. Transect lines were placed perpendicular to the study site's longest axis.
Habitat factors were measured on all 48 clear-cuts. Thirty-three circles with a radius of 5.64 m were placed randomly within each clear-cut. Coverage (%) of exposed mineral soil, woody debris and bare rock were visually estimated. All living stumps of trees over 10 cm in diameter were identified to species level.
Two-tailed t-tests were used to examine possible differences for size (ha), TSC (years), exposed mineral soil (%), woody debris (%), bare rock (%), basal area of coniferous trees ( m2/ha) and basal area of deciduous trees ( m2/ha).
Generalized linear models were used to examine possible differences between historical land use in regards to number of butterfly individuals and species. All of the tests above were calculated using SPSS 22.0.
CANOCO 5 was used to perform multivariate statistical analyses for butterfly species association with historical land use.
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Last updated: 05/28/14