Landscape Features and Processes Influencing Forest Pest Dynamics

Abstract

Insects and pathogens (pests) in forest ecosystems can impact tree fitness and greatly increase rates of tree mortality. Pest dynamics vary significantly across spatial and temporal scales due to influences from a range of landscape features. Here, with a focus on recent research, primarily from coniferous forest ecosystems, I review the influence of landscape features and their interactions with global change pressures on forest pest dynamics. Landscape genetics have revealed evidence of local adaptation and spatially aggregated patterns in phenotypes within tree populations. Thus, I also consider the role of phenotypic adaptations as features of the landscape affecting forest pest dynamics. Landscape influences on pest dynamics are illustrated by three case-studies representing pests with different feeding strategies, levels of host-specialization, and dispersal potential. The effects of landscape features on forest pest-host interactions are anticipated to grow increasingly complicated in an era of rapid environmental change. Despite recent advances in remote sensing, genomics, and analytical tools, significant gaps remain in our understanding of the complex interactions of pest-host systems with landscape features under global change pressures. Filling these gaps requires continued research into the landscape ecology of forest pests, along with increased efforts to understand the role of pest and host functional traits in pest population dynamics. Thus, I conclude with a conceptual framework for generating testable hypotheses regarding factors affecting the relative influence of landscape features on forest pest dynamics and the predictability of spatiotemporal patterns in forest pest dynamics.