Joint effects of habitat heterogeneity and species' life-history traits on population dynamics in spatially structured landscapes.

Xinping Ye,Andrew K Skidmore,Tiejun Wang,Lalit Kumar

doi:10.1371/journal.pone.0107742

Xinping Ye, Andrew K Skidmore + Show 2 more

Open Access

https://doi.org/10.1371/journal.pone.0107742

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Abstract

Both habitat heterogeneity and species’ life-history traits play important roles in driving population dynamics, yet there is little scientific consensus around the combined effect of these two factors on populations in complex landscapes. Using a spatially explicit agent-based model, we explored how interactions between habitat spatial structure (defined here as the scale of spatial autocorrelation in habitat quality) and species life-history strategies (defined here by species environmental tolerance and movement capacity) affect population dynamics in spatially heterogeneous landscapes. We compared the responses of four hypothetical species with different life-history traits to four landscape scenarios differing in the scale of spatial autocorrelation in habitat quality. The results showed that the population size of all hypothetical species exhibited a substantial increase as the scale of spatial autocorrelation in habitat quality increased, yet the pattern of population increase was shaped by species’ movement capacity. The increasing scale of spatial autocorrelation in habitat quality promoted the resource share of individuals, but had little effect on the mean mortality rate of individuals. Species’ movement capacity also determined the proportion of individuals in high-quality cells as well as the proportion of individuals experiencing competition in response to increased spatial autocorrelation in habitat quality. Positive correlations between the resource share of individuals and the proportion of individuals experiencing competition indicate that large-scale spatial autocorrelation in habitat quality may mask the density-dependent effect on populations through increasing the resource share of individuals, especially for species with low mobility. These findings suggest that low-mobility species may be more sensitive to habitat spatial heterogeneity in spatially structured landscapes. In addition, localized movement in combination with spatial autocorrelation may increase the population size, despite increased density effects.

Highlights

Habitat heterogeneity is increasingly recognized as a significant factor affecting the dynamics and persistence of populations [1,2,3,4,5]
All hypothetical species exhibited a constant increase in population size as the scale of spatial autocorrelation in habitat quality increased (Figure 5a)
We explored how habitat spatial autocorrelation interacts with species’ life-history attributes to influence population dynamics within spatially structured landscapes

Summary

Introduction

Habitat heterogeneity is increasingly recognized as a significant factor affecting the dynamics and persistence of populations [1,2,3,4,5]. Defining a landscape as discrete habitat/matrix patches overlooks the spatial pattern of continuously varying habitat quality that might facilitate or constrain the performance of individuals and population dynamics [12,13]. Predictions of population dynamics are influenced by how the spatial variation in habitat quality within a landscape is calculated [14]. In this sense, a continuous representation of habitat quality is expected to more accurately reflect how a species experiences a heterogeneous landscape [15]

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