Effect of spatial scale on factors limiting species distributions in dry grassland fragments
Article first published online: 16 SEP 2004
Journal of Ecology
Volume 92, Issue 5, pages 854–867, October 2004
How to Cite
MÜNZBERGOVÁ, Z. (2004), Effect of spatial scale on factors limiting species distributions in dry grassland fragments. Journal of Ecology, 92: 854–867. doi: 10.1111/j.0022-0477.2004.00919.x
- Issue published online: 16 SEP 2004
- Article first published online: 16 SEP 2004
- Received 15 March 2004 revision accepted 2 June 2004; Handling Editor: David Gibson
- community structure;
- distribution patterns;
- dry grassland;
- metapopulation dynamics;
- patch occupancy;
- perennial herbs;
- seed dispersal;
- sowing experiment;
- species diversity
- 1Distribution of plant species in fragmented landscapes is the result of both seed and site availability. Little is known about how their relative importance differs at different spatial scales.
- 2I sowed seeds of eight dry grassland species into 22 localities that differed in occupancy by these species and followed seedling establishment over 3 years. I compared the number of emerging seedlings at three scales: between previously occupied and previously unoccupied localities, between occupied and unoccupied blocks within occupied localities, and between plots with and without seed addition within occupied blocks.
- 3At the two larger scales, I also studied the relationship of the number of seedlings and of the distributions of adult plants to environmental factors.
- 4Both seed and site availability are important in structuring the distribution of these species, but site availability becomes less important with increasing spatial scale. The intensity of this effect is, however, species specific.
- 5The relationship between environmental factors and pattern of species distribution is also clearly scale dependent, and differs between seedlings and adults. Whilst abiotic factors are the main determinants of seedling distribution, the occurrence of adult individuals is best predicted by the occurrence of other species. This suggests that the present distribution of species in the landscape is determined mainly by historical factors.
- 6Conclusions based on the importance of seed and site availability for species distribution in natural communities at one scale cannot be extrapolated to other scales. Only comparisons on multiple scales can provide a full understanding of factors affecting species distribution at landscape level.