A nutrient-based sustainability assessment of purpose-grown poplar and switchgrass biomass production systems established on marginal lands in Canada

作者：Ashiq Muhammad Waseem; Bazrgar Amir Behzad; Fei Houman; Coleman Brent; Vessey Kevin; Gordon Andrew; Sidders Derek; Keddy Tim; Thevathasan Naresh^*

来源：Canadian Journal of Plant Science, 2018, 98(2): 255-266.

DOI：10.1139/cjps-2017-0220

• marginal lands
• nutrient
• poplar
• sustainability
• switchgrass

The sustainability of purpose-grown biomass production on marginal lands in Canada is uncertain. In this study, an assessment of biomass yield and sustainability was performed for two poplar clones (Poplus deltoides x P. nigra, DN-34-PDN, and P. nigra x P. maximowiczii, NM-6-PNM) and two switchgrass cultivars (Panicum virgatum 'Cave-in-Rock'-SGC, and P. virgatum 'Nebraska'-SGN) on three marginal lands in Guelph (ON), Kemptville (ON), and Nappan (NS) in Canada. The differences in stem biomass across sites were not significant; however, differences in stem biomass among plants were statistically significant between poplar and switchgrass (p < 0.0001) and between poplar clones (p < 0.0001). The 2-yr stem biomass yield in PNM (15.27 +/- 1.28 t ha(-1)) was significantly higher than those in PDN (7.02 +/- 0.54 t ha(-1)), SGC (2.57 +/- 0.28 t ha(-1)), and SGN (1.45 +/- 0.22 t ha(-1)). Two sustainability indices based on macronutrients (MBSI) and nitrogen (NBSI), were developed to assess sustainability. Both indices show that the biomass production system of high-yielding poplar clone PNM depicts nutrient loss and may require external nutrient inputs via fertilization during the establishment phase. Higher index values for switchgrass SGC (1.47 +/- 0.22, 1.11 +/- 0.15) and SGN (1.37 +/- 0.16, 1.17 +/- 0.12) for MBSI and NBSI, respectively, indicate that despite low stem biomass yields, switchgrass biomass production is sustainable. These findings suggest that, from a nutrient perspective, sustainable biomass production systems can be established on marginal lands in Canada; however, there is a trade-off between high yield and long-term sustainability in purpose-grown biomass production systems.

• 出版日期2018-4