Landscape diversity slows the spread of an invasive forest pest species

Abstract

According to the associational resistance hypothesis, diverse habitats provide better resistance to biological invasions than monocultures. Host-plant abundance has been shown to affect the range expansion of invasive pests, but the effect of landscape diversity (i.e. density of host/non-host patches and diversity of forest habitat patches) on invasions remains largely untested. We used boundary displacement models and boosted regression tree analyses to investigate the effects of landscape diversity on the invasion of Corsica by the maritime pine bast scale Matsucoccus feytaudi over an 18-yr period. Taking the passive wind dispersal of the scale into account, we showed that open habitats and connectivity between host patches accelerated spread by up to 13%, whereas landscapes with high tree diversity and a high density of non-host trees decreased scale spread by up to 14%. We suggest a new mechanism for such associational resistance to pest invasion at the landscape level, which we term 'the pitfall effect'. (Résumé d'auteur

Plant neighbour identity and invasive pathogen infection affect associational resistance to an invasive gall wasp

“…This idea received support (Case 1990;Erneberg 1999;Kennedy et al 2002) mainly from plant ecologists (Levine et al 2004), while much less is known about ecosystem resistance to invasive pest insects (Wilsey and Polley 2002). A few recent studies suggest that tree diversity in native communities may reduce the establishment and spread of invasive pests (Rigot et al 2014;Guyot et al 2015), but identifying the underlying mechanisms remains a major challenge (Nunez-Mir et al 2017).…”

Stratégies et potentiel d’invasion des massifs forestiers par <i>Hopea odorata</i> Roxb. (Dipterocarpaceae) : cas du Parc National du Banco en Côte d’Ivoire

“…Le taux moyen de germination dans les sachets de polyéthylène varie de 10 à 50% avec une moyenne de 30 ± 28,93% (Figure 2). (Rigot et al, 2014). Ces informations peuvent servir de levier pour les mesures à prendre dans le contrôle de l'envahissement de cette plante non-indigène (Pyšek et al, 2014).…”

“…Pour notre part, nous n'avons pas étudié la capacité de dispersion spatiale de ce taxon. Cependant, nous pouvons argumenter que malgré la présence d'un massif forestier qui peut constituer un brise-vent naturel (Rigot et al, 2014), l'espèce Hopea odorata arrive à implanter de nouveaux individus dans la périphérie du Parc National du Banco. Cela démontre sa capacité à coloniser de nouveaux territoires et ceci pourrait contribuer à son caractère envahissant dans le Parc National du Banco.…”

Agricultural landscapes with prevailing grasslands can mitigate the population densities of a tree-damaging alien species

“…For example, an alien might damage an economically unimportant ornamental plant. Nevertheless, the latter kind of alien might be a useful model organism for studying the mechanisms of spread and possible pest management and amendments (Rigot et al, 2014).…”