Simulating potential Palmer amaranth distribution under current climate and RCP 8.5 scenario

Authors: Kistner-Thomas, Erica; Hatfield, Jerry

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 5/15/2018
Publication Date: 10/18/2018
Citation: Kistner-Thomas, E.J., Hatfield, J.L. 2018. Simulating potential Palmer amaranth distribution under current climate and RCP 8.5 scenario [abstract]. In: Upper Midwest Invasive Species - North American American Invasive Species Management Association Joint Conference, October 15-18, 2018, Rochester, MN. Available: https://www.umisc.net/.

Interpretive Summary:

Technical Abstract: Palmer amaranth (Amaranthus palmeri) is an invasive annual forb that has recently emerged as one of the most widespread and severe agronomic weeds in the United States, due in part to its facility for evolving herbicide resistance. Originally from the Sonoran Desert regions of northern Mexico and southwestern U.S., this highly adaptive weed has spread across the U.S. due to human-assisted dispersal of its seeds. It has also invaded portions of Africa, Europe, and South America. The distribution and growing season of a weed species like Palmer amaranth will undoubtedly change as a consequence of climate change, adding additional challenges to managing this species. To assess this, we developed a process-oriented bioclimatic niche model of Palmer amaranth using CLIMEX, to examine its potential global distribution under both current climatic conditions and possible future climate under the RCP 8.5 emission scenario for the year 2050. Model projections indicated that key row-crop production regions in Africa and Australia are at high risk for Palmer amaranth invasion in terms of both current conditions and future climate scenarios. In the Northern Hemisphere, projected increases in temperature will likely enable Palmer amaranth to expand its range northward into Canada and northern Europe. In the U.S. alone, suitable range for Palmer amaranth would increase by 21.22% by mid-century, particularly in the central and western states. The results of this study highlight several agricultural production regions of increasing and emerging risk from Palmer amaranth that should be considered routinely in ongoing biosecurity and weed management programs.