The Role of Genetics and Genomics in Riparian Restoration and Management: Insights from Research in Foundation Cottonwood Species
Gerard Allan1,2,3*, Helen Bothwell1,2,4, Scott Woolbright5, Tamara Max1,2, Dana Ikeda1, Samuel Cushman6, Thomas Whitham1,3
1 Department of Biological Sciences, Northern Arizona University, P.O. Box 5640, Flagstaff, Arizona 86011, USA; Gerard.Allan@nau.edu, tamara.max@nau.edu, Dana.Ikeda@nau.edu, Thomas.Whitham@nau.edu
2 Environmental Genetics & Genomics Core Facility, Northern Arizona University, P.O. Box 5640, Flagstaff, Arizona 86011, USA
3 Merriam Powell Center for Biodiversity, Northern Arizona University, P.O. Box 5640, Flagstaff, Arizona 86011; USA
4 The Australian National University, College of Science, Canberra, AU Helen.Bothwell@anu.edu.au
5 College of Arts, Letters and Sciences, University of Arkansas, Little Rock, Little Rock, AR 72204, USA; sawoolbright@ualr.edu
6 U.S. Forest Service, Rocky Mountain Research Station, Northern Arizona University, Flagstaff, AZ 86011, USA; scushman@fs.fed.us
*Corresponding author: Gerard.Allan@nau.edu, Tel.: 928-523-8934. Fax: 928-523-5311, USA
Genetic and genomic information is playing an increasingly important role in understanding how foundation species respond to environmental perturbations, including exotic species invasion and climate change. In many cases, these responses include changes in the genetic makeup of foundation tree populations and corresponding changes in how genetic diversity is distributed across riparian corridors. New methods and analysis tools are providing insight into the factors that shape genetic variation, including assessments of how gene flow is facilitated or impeded within a species’ distribution, and the identification of genes involved in key ecological interactions. Incorporating this information into genetic models also enhances our ability to predict how foundation species will respond to environmental change, which in turn, can lead to improved management strategies. These strategies will better account for changes in the genetic makeup of riparian species, whether they are threatened by exotic species invasion (e.g, tamarisk), increased drought, or a combination of both. The development of genetic-based management strategies can also have important implications for the maintenance and preservation of biodiversity in riparian ecosystems as many dependent communities track genetic variation in foundation trees. The resulting network comprises an interdependent web of gene x environment interactions that establish important feedbacks relating to the long-term maintenance, stability and function of riparian ecosystems.