资源环境科技发展态势分析平台

Multiple use of communal forests requires informed management to balance divergent interests such as livestock grazing and timber production. In this study, we examined the habitat selection of free-ranging beef cattle in two vegetation-mapped communal forests of Norway's boreal zone. The two areas were 35 km apart, and they mainly differed regarding cattle stocking density, with one being below and the other above the livestock grazing capacity of the area. In total, 78 cows were fitted with global positioning system (GPS) collars during the summers 2015 to 2017. The collars were scheduled to take positions and measure activity at 5 and 10 min intervals. We applied generalized linear mixed models (GLMM) to describe the cows' selection of vegetation types, forest cutting classes, topographical features and distance to roads with resource selection functions (RSF), by comparing use with availability. The most selected vegetation types were wide-spread summer farm meadows, followed by the dominant bilberry spruce forest. In productive forest, the cows selected for clearcuts younger than 15 years and used thinning and post-thinning stands less than expected. In accordance with the Ideal free distribution hypothesis, the cows were more likely to use low productive habitats in the area with high compared to the one with low stocking density. The preference for young forest stands was strongest when grazing as compared to resting and walking. During grazing, the cows also preferred pre-thinning stands older than 15 years and inclined patches, but avoided north-facing slopes. Preference for south-facing slopes was strongest when resting and for forest roads when traveling.

To reduce the pressure of cattle in forest regeneration stands, we suggest limiting stocking densities to the grazing capacity of forest pastures, using vegetation and forest maps as information to guide the distribution of cattle, and maintaining or even expanding the existing meadows of the summer farms.