Campus Units

Agronomy

Document Type

Article

Publication Version

Published Version

Publication Date

9-2012

Journal or Book Title

GCB Bioenergy

Volume

4

Issue

5

First Page

534

Last Page

544

DOI

10.1111/j.1757-1707.2011.01153.x

Abstract

The first replicated productivity trials of the C4 perennial grass Miscanthus × giganteus in the United States showed this emerging ligno-cellulosic bioenergy feedstock to provide remarkably high annual yields. This covered the 5 years after planting, leaving it uncertain if this high productivity could be maintained in the absence of N fertilization. An expected, but until now unsubstantiated, benefit of both species was investment in roots and perennating rhizomes. This study examines for years 5–7 yields, biomass, C and N in shoots, roots, and rhizomes. The mean peak shoot biomass for M. × giganteus in years 5–7 was 46.5 t ha−1 in October, declining to 38.1 t ha−1 on completion of senescence and at harvest in December, and 20.7 t ha−1 declining to 11.3 t ha−1 for Panicum virgatum. There was no evidence of decline in annual yield with age. Mean rhizome biomass was significantly higher in M. × giganteus at 21.5 t ha−1compared to 7.2 t ha−1 for P. virgatum, whereas root biomass was similar at 5.6–5.9 t ha−1. M. × giganteus shoots contained 339 kg ha−1 N in August, declining to 193 kg ha−1 in December, compared to 168 and 58 kg ha−1 for P. virgatum. The results suggest substantial remobilization of N to roots and rhizomes, yet still a substantial loss with December harvests. The shoot and rhizome biomass increase of 33.6 t ha−1 during the 2-month period between June and August for M. × giganteus corresponds to a solar energy conversion of 4.4% of solar energy into biomass, one of the highest recorded and confirming the remarkable productivity potential of this plant.

Comments

This article is published as Dohleman, Frank G., Emily A. Heaton, Rebecca A. Arundale, and Stephen P. Long. "Seasonal dynamics of above‐and below‐ground biomass and nitrogen partitioning in Miscanthus× giganteus and Panicum virgatum across three growing seasons." Gcb Bioenergy 4, no. 5 (2012): 534-544. doi: 10.1111/j.1757-1707.2011.01153.x. Posted with permission.

Creative Commons License

Creative Commons Attribution 4.0 License
This work is licensed under a Creative Commons Attribution 4.0 License.

Copyright Owner

Blackwell Publishing Ltd

Language

en

File Format

application/pdf

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