Differences in spatial autocorrelation (SAc), plant species richness and diversity, and plant community composition in grazed and ungrazed grasslands along a moisture gradient, North Dakota, USA
Article first published online: 17 APR 2013
© 2013 International Association for Vegetation Science
Applied Vegetation Science
Volume 17, Issue 1, pages 53–62, January 2014
How to Cite
Meyers, L. M., DeKeyser, E. S., Norland, J. E. (2014), Differences in spatial autocorrelation (SAc), plant species richness and diversity, and plant community composition in grazed and ungrazed grasslands along a moisture gradient, North Dakota, USA. Applied Vegetation Science, 17: 53–62. doi: 10.1111/avsc.12040
- Issue published online: 16 DEC 2013
- Article first published online: 17 APR 2013
- Manuscript Accepted: 18 MAR 2013
- Manuscript Received: 1 OCT 2012
- Spatial structure;
- Invasive species;
- Prairie/grassland Management
How are plant species richness and diversity related to spatial autocorrelation under grazed and ungrazed conditions in grassland communities? Is spatial autocorrelation dissimilar within different plant communities?
The grasslands of southeast North Dakota, USA.
The study was conducted during the summer of 2009 in six grasslands under different management (grazed vs ungrazed with fire) along a moisture gradient. Spatial autocorrelation at each site was measured along 50-m transects among three different landscape positions representing different moisture levels. Dissimogram multivariate analysis was used to measure the nugget, dissimilarity and patch diameter. Additionally, richness and Shannon diversity indices and nonmetric multidimensional scaling analysis were compared to the dissimogram results.
Mean patch diameter was significantly higher in grazed mid-slope sites than in ungrazed sites. Spatial autocorrelation was not different between the landscape positions (higher, dry areas were not different from lower, mesic areas). However, plant species richness, diversity and community composition were found to be different between landscape positions and management, with key differences in the presence of certain invasive species.
Disturbance and moisture level were reflected differently in the spatial autocorrelation analysis compared to the richness, diversity and ordination analyses. This indicates that disturbance and management impacted spatial autocorrelation separate from plant community composition and species diversity. This also highlights changes in the plant community caused by different management actions and the spread of invasive species.