Staggered nested designs to assess scales of variability: the advantages of a spatially explicit analysis
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A staggered nested sampling design was used to identify spatial scales of variation in the abundance of an intertidal clam Austrovenus stutchburyi. A georeferenced sampling design permitted assessment of abundance at spatial lags between 0.1 and 87 m. An analysis of variance approach produced imprecise estimates of variability, whereas spatially explicit analyses improved the resolution greatly. A geostatistical model identified the spatial scale of residual variance as 13 m and that of the asymptote of spatial dependence as 17 m. It also permitted mapping of bivalve abundance. Staggered nested designs are highly efficient for comparing hierarchies of scale, but in this study analysis of detailed positional information was required to tease out useful spatial information.
KeywordsClam Geostatistics Scale Spatial pattern Staggered nested design
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- Bainbridge, T. R. (1965). Staggered nested designs for estimating variance components. Industrial Quality Control, 22, 12–20.Google Scholar
- Cole, R. G. (2001). Staggered nested designs to estimate hierarchical levels of variability. New Zealand Journal of Marine and Freshwater Research, 35(5), 891–896.Google Scholar
- Dobbie, N. J. (1996). Benthic fauna of Pine Harbour Marina. MSc thesis, University of Waikato, New Zealand.Google Scholar
- McArdle, B. H. & Pawley, M. D. M. (1994). Cost-benefit analysis in the design of biological monitoring programmes: Is it worth the effort? In D. J. Fletcher & B. F. J. Manly (Eds.), Statistics in ecology and environmental monitoring (pp. 239–253). Dunedin: University of Otago Press.Google Scholar
- Naik, D. N., & Khattree, R. (1998). A computer program to estimate variance components in staggered nested designs. Journal of Quality Technology, 30, 292–297. http://www.stat.unipg.it/pub/stat/statlib/jqt/30-3.Google Scholar
- Nelson, L. S. (1983). Variance estimation using staggered, nested designs. Journal of Quality Technology, 15, 195–198.Google Scholar
- Robertson, G. P. (1998). GS+: Geostatistics for the environmental sciences. Plainwell, Michigan USA: Gamma Design Software.Google Scholar
- Underwood, A. J. & Denley, E. J. (1984). Paradigms, explanations and generalizations in models for the structure of intertidal communities on rocky shores. In D. R. Strong, D. Simberloff, L. G. Abele & A. B. Thistle (Eds.), Ecological communities: Conceptual issues and the evidence (pp. 151–180). New Jersey, USA: Princeton University Press.Google Scholar