Callen, Steven , Jimenez, Ivan , Knouft, Jason , Miller, Allison .
Climatic niche shift in kudzu, Pueraria montana var. lobata, upon invasion into North America.
While economic and ecological costs associated with biological invasions are significant, the majority of introductions are unsuccessful. Introduction success or failure depends upon several complicating factors, including biotic interactions, anthropogenic influences, and climatic conditions. At the onset of a biological invasion, climate matching may initially increase the probability of successful introduction and establishment, and then serve as an important factor for the subsequent spread of the invading species. Species distribution models (SDMs), which combine observed species records with their associated climatic conditions, are frequently used to predict the current or future presence of a species in a geographical area and are therefore important tools for predicting biological invasions. Single-species niche conservatism is an underlying assumption of both climate matching and SDMs. Recent evidence suggests niche conservatism may be an important factor for many biological invasions, but that niche shifts may also occur upon invasion. It is currently unknown if one of the most pervasive and aggressive introduced species in North America, kudzu (Pueraria montana var. lobata), exhibits niche conservatism or niche shift upon invasion. Native to Asia, kudzu was introduced into North America in 1876 and has since established populations in nearly 30 states. To identify differences in native and introduced climatic niches that may be contributing to kudzu's success in North America, GIS-based techniques were used to characterize the climatic niches of native and introduced kudzu populations in both geographic and environmental space (G- and E-space, respectively). Niche overlap, equivalency, and similarity metrics based on Schoener's D were used to quantify differences between the climatic niches in G-space, whereas a between-class inertia percentage was used to characterize the difference in E-space. Annual precipitation was the most important variable characterizing both ranges. Temperature seasonality was important for predicting the extent of the native range, while precipitation of the driest month and annual mean temperature were important for predicting the introduced range. Niche metrics indicated little overlap and similarity of the climatic niches. While biotic and anthropogenic factors likely play a role in kudzu's invasion, these preliminary results suggest different abiotic factors characterize the native and introduced niches of kudzu.
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Saint Louis University Biology - Miller Lab
1 - Saint Louis University, Department of Biology, 3507 Laclede Avenue, St. Louis, MO, 63103, USA
2 - Missouri Botanical Garden, CCSD, P.O. Box 299, St. Louis, MO, 63166, USA
ecological niche modelling
Pueraria montana var. lobata.
Presentation Type: Oral Paper:Papers for Sections
Date: Monday, July 9th, 2012
Time: 11:00 AM