Sample shape, spatial scale and species counts: Implications for reserve design

doi:10.1016/S0006-3207(97)00042-6

Biological Conservation

Volume 82, Issue 3, December 1997, Pages 369-377

https://doi.org/10.1016/S0006-3207(97)00042-6 Get rights and content

Abstract

The optimal design of nature reserves has been a hotly debated topic for some years. One contentious issue has concerned the ideal shape of reserves, with several researchers suggesting that reserves should be as nearly circular as possible to minimize edge-related degredation and potential ‘peninsularity’ effects. This paper demonstrates an advantage to non-circular reserves: given the spatial autocorrelation of environmental conditions and species ranges, elongated samples should tend to capture a greater diversity of conditions and, consequently, a greater number of species. To test this idea, samples of 16 cells, arranged as 4 × 4 squares, 2 × 8 rectangles and 1 × 16 lines were considered in mapped plant distributions at spatial scales ranging from cells of 1 m² to 2500 km². Overall, elongated samples tended to capture significantly larger numbers of species than did their square counterparts, as predicted. The degree of elongated sample advantage was very similar at all but the smallest of the scales considered, suggesting that the pattern of species turnover (β-diversity) is nearly scale-independent or fractal in nature. As the advantages of elongation are largely scale-independent and the only documented disadvantages (edge effects) are very scale-dependent, the optimal shape of a reserve for species sampling should shift as a function of reserve size, with large reserves becoming increasingly elongated.

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Sample shape, spatial scale and species counts: Implications for reserve design

Abstract

Biol. Conserv.

Biol. Conserv.

J. Theor. Biol.

Biol. Conserv.

Ecol. Model.

Biol. Conserv.

Biol. Conserv.

Trends Ecol. Evol.

Biol. Conserv.

Trends Ecol. Evol.

Biol. Conserv.

Predation on artificial nests adjacent to forestry plantations in northern Scotland

Oikos

The spatial structure of the physical environment

Oecologia

Is there a best shape for nature reserves?

Biol. Conserv.

Forest fragmentation and alien plant invasion of central Indiana old-growth forests

Conserv. Biol.

Spatial aspects of ecological data

Is the peninsular effect a red herring?

Am. Nat.

Flora of the East Riding of Yorkshire

Zoogeography: The Geographical Distribution of Animals

The design of a nature reserve system for Indonesian New Guinea

Island biogeography and the design of nature reserves

Flora of Hertfordshire

Protected areas in the United Kingdom: an approach to the selection, establishment and management of natural and scenic protected areas in a densely populated country with limited choices

Vegetation responses along edge-to-interior gradients in the mixed hardwood forests of the Roanoke River basin, North Carolina

Conserv. Biol.

Best shape for nature reserves

Nature

The Flora and Vegetation of County Durham

Sussex Plant Atlas

Fractals: A User's Guide for the Natural Sciences

Island biogeography theory and nature reserve design

J. Biogeogr.

The species-area relations of plant communities

J. Ecol.

Spatial variance in ecology

Oikos

Atlas of the Devon Flora