Bruun Hans Henrik, Fritzbøger Bo
Botanical Institute, University of Copenhagen, Øster Farimagsgade 2D, 1353 Copenhagen K, Denmark.
Ambio. 2002 Aug;31(5):425-31. doi: 10.1579/0044-7447-31.5.425.
The recent decline in species richness in (semi)-natural habitats in northern Europe has largely been attributable to habitat destruction, and to subsequent limitation in seed dispersal among fragments. However, some habitat types were probably split up already in the historical landscape, but the segregated parts were probably not isolated to the present degree. This paper seeks evidence for livestock as vectors for propagules at 3 spatial scales in the past cultural landscape. Three main scales at which livestock acted as seed dispersers are important: free movement in the landscape (1-10 km), driving animals to mast feeding or to manors (10-50 km), and the export of living animals (hundreds of km). The emerging picture is for most plant species a dramatically decreased chance of dispersal in the modern landscape. The consequence is probably decreasing species richness in (semi)-natural plant communities, such as pasture, meadow, and heathland.
北欧（半）自然栖息地物种丰富度最近的下降主要归因于栖息地破坏以及随后碎片间种子传播的受限。然而，一些栖息地类型在历史景观中可能就已被分割，但隔离的部分可能并未达到目前的孤立程度。本文旨在寻找证据，证明在过去的文化景观中，家畜在三个空间尺度上作为繁殖体载体的作用。家畜作为种子传播者的三个主要尺度很重要：在景观中的自由移动（1 - 10公里）、驱赶动物去觅食或前往庄园（10 - 50公里）以及活体动物的出口（数百公里）。新出现的情况是，对于大多数植物物种来说，在现代景观中传播的机会大幅减少。其后果可能是（半）自然植物群落（如牧场、草地和石南荒地）的物种丰富度下降。
