Forecasting spatially structured populations: the role of dispersal and scale

Cailin, Xu and Boyce, Mark S and Gadgil, Madhav and Nanjundiah, Vidyanand (2005) Forecasting spatially structured populations: the role of dispersal and scale. In: Journal of Theoretical Biology, 233 (2). pp. 177-189.

PDF sdarticle.pdf - Published Version Restricted to Registered users only Download (526kB) | Request a copy

Abstract

We forecasted spatially structured population models with complex dynamics. focusing on the effect of dispersal and spatial scale on the predictive capability of nonlinear forecasting (NLF). Dispersal influences NLF ability by its influence on population dynamics. For simple 2-cell models, when dispersal is small, our ability to predict abundance in subpopulations decreased and then increased with increasing dispersal. Spatial heterogeneity, dispersal manner. and environmental noise did not qualitatively change this result. But results are not clear for complex spatial configurations because of complicated dispersal interactions across subpopulations. Populations undergoing periodic fluctuations could be forecasted perfectly for all deterministic cases that we studied, but less reliably when environmental noise was incorporated. More importantly, for all models that we have examined, NLF was much worse at larger spatial scales as a consequence of the asynchronous dynamics of subpopulations when the dispersal rate was below some critical value. The only difference among models was the critical value of dispersal rate. which varied with growth rate, carrying capacity, mode of dispersal, and spatial configuration. These results were robust even when environmental noise was incorporated. Intermittency, common in the dynamics of spatially structured populations, lowered the predictive capability of NLF. Forecasting population behaviour is of obvious value in resource exploitation and conservation. We suggest: that forecasting at local scales holds promise, whereas forecasting abundance at regional scales may yield poor results. Improved understanding of dispersal can enhance the management and conservation of natural resources. and may help is to understand resource-exploitation strategies employed by local indigenous humans.

Item Type:	Journal Article
Publication:	Journal of Theoretical Biology
Publisher:	Elsevier Science
Additional Information:	Copyright of this article belongs to Elsevier Science.
Keywords:	Nonlinear forecasting;Spatially structuredpopulations;Dispersal;Spatial scale;Resource exploitation.
Department/Centre:	Division of Physical & Mathematical Sciences > Centre for Theoretical Studies (Ceased to exist at the end of 2003) Division of Biological Sciences > Centre for Ecological Sciences
Date Deposited:	22 Jul 2009 07:50
Last Modified:	19 Sep 2010 04:55
URI:	http://eprints.iisc.ac.in/id/eprint/17044

Actions (login required)

View Item