Establishment of Regional Phytoremediation Buffer Systems for Ecological Restoration in the Great Lakes Basin, USA. I. Genotype × Environment Interactions

Ronald S Zalesny,Andrej Pilipović,Ryan A Vinhal,Neil D Nelson,Mike Peterson,Larry Buechel,Chung-Ho Lin,Edmund O Bauer,Joel G Burken,Ray Seegers,Richard A Hallett,Brent S Debauche,Bernard G Mcmahon,Elizabeth R Rogers,Adam H Wiese

doi:10.3390/f12040430

Abstract

Poplar remediation systems are ideal for reducing runoff, cleaning groundwater, and delivering ecosystem services to the North American Great Lakes and globally. We used phyto-recurrent selection (PRS) to establish sixteen phytoremediation buffer systems (phyto buffers) (buffer groups: 2017 × 6; 2018 × 5; 2019 × 5) throughout the Lake Superior and Lake Michigan watersheds comprised of twelve PRS-selected clones each year. We tested for differences in genotypes, environments, and their interactions for health, height, diameter, and volume from ages one to four years. All trees had optimal health. Mean first-, second-, and third-year volume ranged from 71 ± 26 to 132 ± 39 cm3; 1440 ± 575 to 5765 ± 1132 cm3; and 8826 ± 2646 to 10,530 ± 2110 cm3, respectively. Fourth-year mean annual increment of 2017 buffer group trees ranged from 1.1 ± 0.7 to 7.8 ± 0.5 Mg ha−1 yr−1. We identified generalist varieties with superior establishment across a broad range of buffers (‘DM114’, ‘NC14106’, ‘99038022’, ‘99059016’) and specialist clones uniquely adapted to local soil and climate conditions (‘7300502’, ‘DN5’, ‘DN34’, ‘DN177’, ‘NM2’, ‘NM5’, ‘NM6’). Using generalists and specialists enhances the potential for phytoremediation best management practices that are geographically robust, being regionally designed yet globally relevant.

Highlights

Ninety-five percent of the United States’ surface freshwater and 20% of the world’s freshwater reserve are contained within the Great Lakes Basin [1,2]
The sites ranged in latitude from 46.7840 to 42.8382 ◦ N and in longitude from −89.1291 to −86.5976 ◦ W, which is consistent with poplar productivity supplysheds in the region [47,59,60,61]
Understanding genotype by environment (G × E) interactions is a necessary step for identifying and selecting poplar clones used for phytoremediation and associated phytotechnologies [68]

Summary

Introduction

Ninety-five percent of the United States’ surface freshwater and 20% of the world’s freshwater reserve are contained within the Great Lakes Basin [1,2]. The Basin provides ecosystem services (including clean drinking water) to over 34 million people in the United. Non-point sources of pollution such as landfills and similar sites contribute to watershed contamination by runoff and leakage. Pollutant levels within landfills generally decrease over time through chemical and biological alteration and degradation [11,12,13], treatment of leachate and wastewaters can help mitigate soil and water contamination [14]. Sustainable, long-term restoration practices are needed to preserve and enhance ecosystem services in the Great Lakes Basin

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Conclusion