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Biomass for biofuel: Understanding the risks and

opportunities for Ontario agriculture.

Journal: Canadian Journal of Plant Science

Manuscript ID CJPS-2016-0401.R1

Manuscript Type: Special Issue Paper (Please select below)

Date Submitted by the Author: 18-Sep-2017

Complete List of Authors: Deen, Bill

Keywords: crop residues, C4 perennial grass, Biomass, crop rotation, land classification

https://mc.manuscriptcentral.com/cjps-pubs

Canadian Journal of Plant Science

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Biomass for biofuel: Understanding the risks and opportunities for Ontario agriculture.

1 Department of Plant Agriculture, University of Guelph, Guelph, ON, Canada N1G 2W12

* Corresponding author: Bill Deen.

E-mail address: [email protected]

Telephone: +1 (519) 824 4120 x53397

Abstract

Markets for biomass are emerging across Canada however considerable concern has been

expressed regarding the ability of Canada's arable land base to sustainably meet this emerging

demand. Using Ontario as a case study, economic and environmental considerations that must

be considered when designing biomass production systems based on either crop residues from

maize (Zea mays L.), soybean (Glycine max (L.) Merr.), or winter wheat (Triticum aestivum L.),

or on dedicated biomass crops, such as miscanthus (Miscanthus spp.) or switchgrass (Panicum

virgatum) are reviewed. The Ontario agricultural land base is characterized by a growing

prevalence of maize/soybean rotations, a high percentage of total arable land under the Canada

Land Inventory categorized as Class 1 and 2, and geographically dispersed Class 3-5 land.

Economic and environmental risks and opportunities of biomass production are demonstrated to

be a function of the source of biomass, land availability, land classification, and existing land use

patterns.

Key words: crop residue, C4 perennial grass, biomass, crop rotation, land classification

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Introduction

Markets for biomass for biofuel are emerging in Ontario and across Canada, including

biomass for heat and/or electricity for industrial, institutional, agricultural or residential users,

liquid fuels for transportation, and gaseous fuels for conversion to heat or electricity. Concern

has been expressed regarding the ability of the existing arable land base in the province, which in

2011 consisted of approximately 3.6M hectares of predominantly maize (Zea mays L.), soybean

(Glycine max (L.) Merr.), winter wheat (Triticum aestivum L.), and forage and pasture (Statistics

Canada, Census of Agriculture. 2016) to sustainably meet this emerging demand. Increasingly

biomass production is being viewed as both an opportunity and a potential risk for agriculture.

In the primary agricultural regions of Ontario the main candidates for biomass for these

emerging markets are 1) crop residues removed from existing crop rotations (e.g. maize, soybean

of wheat crop residue removed by baling), or 2) dedicated biomass crops (e.g. miscanthus,

switchgrass or energy maize). Location of production of both types of biomass, and the

implication of their production on sustainability will be dependent on land capability and

existing cropping system which is correlated with land capability.

In Canada, land capability is determined using the Canada Land Inventory (CLI) for

agriculture (Agriculture and Agri-Food Canada, 2013). CLI is an interpretative system for

assessing the effects of climate and soil characteristics on the limitations of land for growing

common field crops. Class 1 soils have no significant limitations in use for crop production.

The soils are deep, are well to imperfectly drained, hold moisture well, and in the virgin state

were well supplied with plant nutrients. They can be managed and cropped without difficulty.

Under good management they are moderately high to high in productivity for a wide range of

field crops. Class 2 soils have moderate limitations, and moderate conservation practices are

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required to achieve moderately high to high in productivity. Class 3 soils have moderately

severe limitations and the range of crops is restricted or special conservation practices are

required. Class 4 soils have severe limitations. Class 5 soils are restricted to forage crops and

improvement practices are feasible. Figure 1, shows the distribution of Class1-5 land in the

primary agricultural regions of Ontario. It can be seen that Ontario has considerable acreage of

Class 1-3 land. The majority of annual crop production occurs on Class 1-3 soils and maize-

soybean are increasingly the dominant annual crop rotation (Gaudin et al, 2015a).

Approximately 75% of total acreage of annual row crop production is either maize or soybean,.

Class 4-5 soils are predominantly used for pasture and forage production. As can be seen in

Figure 1, Class 4-5 soils are more geographically dispersed than Class 1-3 soils.

Since annual row crop production systems occur predominantly on Class 1-3 land, crop

residue removal will necessarily be associated with this land capability class In contrast,

production of dedicated biomass crops are being considered across all Classes of land. Since

there is little opportunity, other than the Northern Clay Belt, to bring additional land into

production (Ontario Ministry of Natural Resources, 2012), introduction of dedicated crops will

almost certainly require displacement of existing annual or perennial crops.

The objective of this paper is to evaluate economic and environmental risks and

opportunities of biomass derived from crop residues or dedicated biomass crops given land

availability, land classification, and existing land use patterns of agricultural land in Ontario

Crop Residues

Maize, soybean and winter wheat are the main candidates for crop residue removal.

Based on 0.8M, 1.0M and 0.44M hectares of maize, soybean and winter wheat grown in 2011,

respectively, and five-year (2004 to 2008) average yields, aboveground crop residue biomass

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yields for maize, soybean and winter wheat are 8.6, 2.6 and 4.6 Mg ha-1 (Kludze et al., 2013b).

Maize cobs are another biomass option. Cobs can be harvested in a one-pass system with

commercially available modified combines that collect cobs into a trailing wagon (Figure 2).

Based on a cob to grain ratio of 0.16 and a five-year (2004–2008) average maize grain yield,

potential cob yield is 0.9 to 1.4 Mg ha–1 (Kludze et al., 2013b). Based on these estimates,

complete removal of all above-ground crop residues from these three crops would yield 11.5

million Mg y-1 of biomass. While complete removal is technically feasible, it would have

significant ecological, soil health and erosion implications, so complete removal is unlikely to be

advocated.

Acreage of spring cereals, forages and pasture has declined substantially in the past

decades (Figure 3). During the period from 1970 to 2014, forage and spring cereal acreage

declined by approximately 35 and 80% respectively. Decline in forages and pastures is in part

due to a reduction in the beef industry, and also reductions in utilization of perennial forages by

the dairy industry. As has been observed in Wisconsin, the Ontario dairy industry which is

predominantly located on Class 1-3 land is increasingly relying on maize silage to meet feed

requirements as dairy herd size increases (Rankin, 2016). In Ontario, maize-soybean rotations

are now predominant on class 1-3 soils. This predominance of maize and soybean is not unique

to Ontario but also is observed across the Northern Corn Belt. For example, in 2013, maize and

soybean represented approximately 92.1, 74.2, 60.3% of the total harvested area grown in Iowa,

Minnesota and Michigan, respectively (Gaudin et al., 2015a).

Simplification of rotation diversity has had profound impacts on system functioning and

ultimately the feasibility to sustainably remove crop residues. Results from long term research

trials located in Ontario have contributed to growing evidence that clearly demonstrates that

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simple maize/soybean rotations when compared to more complex rotations that include winter

wheat with and without a cover crop, or a forage have a number of negative attributes. Simple

rotations are associated with reduced yield (Meyer-Aurich et al., 2006a, Gaudin et al., 2015b),

increased yield instability (Gaudin et al., 2015b), increased sensitivity to drought (Gaudin et al.,

2015b), reduced soil organic matter (SOM) (Meyers et al., 2006b; Van Eerd et al., 2014),

poorer soil structure as measured by visual and physical measures including aggregate stability

(Munkholm et al., 2013; Congreves et al., 2015), reduced diversity of soil biological

communities (Tiemann et al., 2015), increased nitrogen requirement (Davis et al., 2012; Gaudin

et al., 2015a), reduced input use efficiency, increased GHG emissions (Meyer-Aurich et al.,

2006b), reduced opportunity to utilize cover crops, and reduced success with no-till/reduced till

systems (Meyer Aurich et al., 2006a; Pittelkow et al., 2014).

It is anticipated that yield reduction and yield variability associated with simple rotations

will increase in magnitude in coming years and that this could further constrain the feasibility of

removing crop residue from simple rotations. Moisture constraints that underlie yield reductions

and yield variability of simple rotations could become more prevalent for two reasons. 1)

Changing climate is resulting in warmer growing seasons with more extreme precipitation

patterns in the mid latitude regions (IPPC, 2013). From the 2000-2014 period excessive heat and

drought were shown to decrease mean yield and yield stability in four maize producing States in

the United States (Williams et. at., 2016). 2) Increases in yield potential of maize and soybean

will increase crop water requirements (Richards, 2000) effectively increasing the probability of

water being the yield limiting resource. Soils associated with more complex crop rotations and

corresponding higher levels of SOM tend to have greater plant water availability and will be less

vulnerable to these moisture constraints.

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When determinations of sustainable removal level for crop residues are made, the impact

of crop residue removal on SOM is typically considered. Crop residue requirements to maintain

SOM and nutrient pools are generally higher than those required to control soil erosion (Varvel

and Wilhelm, 2008); thus, sustainable crop residue removal levels are often determined by an

objective to maintain SOM levels. This objective furthermore recognizes the importance of

SOM in maintaining soil health and crop productivity, through such factors as soil water holding

capacity (Williams et al., 2016).

Kludze et al. (2013b) estimated how much crop residue can be removed from Ontario

cropping systems while maintaining SOM at a level of 3%, a level which represent an assumed

“average” SOM for a typical Ontario soil (Table 1). Based on a review of the literature they

determined that the annual SOM mineralization rate across a range of soils is 2-2.5%, and the

annual rate of SOM formation from reside input is 10-20%. Using these ranges they estimated

residue removal levels for three scenarios 1) low SOM mineralization rate and high SOM

formation rate - “best case scenario” for residue removal, 2) average SOM mineralization rate

and average SOM formation rate – “average case scenario” for residue removal and 3) high

SOM mineralization rate and low SOM formation rate - “worst case scenario” for residue

removal. A fourth scenario for residue removal was estimated using SOM mineralization and

SOM formation rates derived from a long-term rotation trial located at the Elora Research

Station, For this scenario mineralization rate and formation rate for SOM was estimated to be

2.5 and 15.1%, respectively. Using these four scenarios, crop residue removable rates that

maintained SOM at 3% were then determined using an approach that accounted for regional

differences in crop yield as well as differences in crop rotation. The amount of residue that

could be sustainably removed was very dependent on assumptions of mineralization rate and

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formation rate of SOM. Using the estimates derived from the long-term rotation trial at Elora,

approximately 1.1 million Mg yr-1 of crop residue can be removed from Ontario agricultural land

without reducing SOM levels below the assumed 3% level. However, if literature average values

for SOM mineralization rate and SOM formation rate were used then approximately 1.92 million

Mg yr-1 could be removed. It was also observed that the amount of residue that could be

removed was dependent on region, with the regions of Southern and Western Ontario enabling

higher residue removal due to larger acreages of crop production, and higher per acre removal

amounts due to higher crop yield and greater rotation complexity. Rotations of

maize/soybean/winter wheat enabled larger amounts of residue removal than rotations consisting

of just maize/soybean.

Maize/soybean is an increasingly common rotation in Ontario and has previously been

associated with lower SOM levels relative to more complex rotations. Crop residue removal

from maize/soybean rotations could accentuate the already documented concerns of relatively

low SOM in this rotation. If crop residues are pursued as a biomass source and removed from

Class 1-3 land, in order to reduce negative impacts on soil and crop productivity Kludze et al.

(2013b) concluded that the following principals should be applied: 1) Crop residues should

preferentially be removed from complex rotations, 2) Cover crops use should be encouraged to

offset effects of crop residue removal, 3) Management practices to increase/maintain crop yield

should be encouraged, 4) Crop residue removal should not necessarily be isolated to no-tillage

systems as no-till production systems are not consistently associated with elevated SOM (Deen

and Kataki, 2003, Powlson et al. 2014) due, in part, to the fact that grain yield under no-till tends

to be lower that under tilled systems (Pittelkow et al., 2014). Crop residue removal should occur

preferentially from no-till systems if the yield lag typically associated with no-till is eliminated.

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While cover crop use is encouraged to offset crop residue removal effects on SOM, it is

unlikely that cover crops integrated into a maize/soybean rotation will be effective in mitigating

negative impacts of crop residue removal. Cover crops in a maize soybean rotation produce

relatively small amounts of biomass due to the effect of high yielding/long season maize hybrids,

low residual nitrogen, combines equipped with stalk chopping/mulching heads that smother

interseeded cover crops, increased yield response to tillage for both maize and soybean when

grown in a simple rotation thereby reducing ability for over-wintering of cover crops and spring

biomass accumulation, and early planting of both maize and soybeans (Vanhie et al., 2015).

Independent of crop residue removal concerns on crop productivity and soil health there

are a number of technical challenges associated with crop residue removal that may limit their

use. While winter and spring cereal crop residue removal is a common and developed practice,

large scale removal of maize and soybean crop residues poses challenges under the Ontario

environment. Full season maize hybrids and soybean varieties are grown to maximize the

growing period and yield potential, consequently planting occurs as early as field conditions

permit in the spring and harvest occurs late in the season. Spring collection of maize crop

residue can interfere with timeliness of subsequent planting operations or may cause soil

compaction if conducted when soil have not had sufficient time to dry following saturated

winter/early spring conditions. Fall collection of maize and soybean crop residues may interfere

with fall operations, for example, soybean crop residue collection may result in winter wheat

planting delays which are associated with reduced winter survival, spring vigour and yield. Late

season collection of maize and soybean crop residues also increases the probability of high

moisture levels in crop residue requiring either drying of crop residues or increased risk of

storage losses. Maize and soybean crop residues, depending on method of collection, also have

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a high probability of contamination by soil which may limit market opportunities. Crop residue

in maize fields following grain harvest is often trampled and in contact with soil (Figure 2c) and

the stalk may still be attached. Chopping of stalks and/or raking of crop residue into a windrow

may be required prior to baling (Figure 2d). Soybean is harvested with a cutter bar positioned

near the soil surface to enable harvesting of pods positioned low on the stem (Figure 2b).

Soybean stem tissue at the surface has a high probability of being contaminated by soil by rain

splash. Collection of maize crop residue may require chopping and/or raking to form a windrow

which could also increase risk of soil contamination. Although maize cob crop residue is less

prone to contamination since it is collected immediately after passing through the combine

(Figure 2a), cob moisture content at harvest is 25% (% weight) or greater which, like maize and

soybean crop residue, may necessitate drying or increased risk of storage losses. Winter wheat

crop residue is harvested at a time of year when it is much easier to ensure moisture levels are

suitable for safe storage. Also since wheat crop residue can be cut at a height above the soil that

avoids soil contamination and all the crop residue flows through the combine and is deposited in

a windrow immediately, risk of soil contamination is reduced. A potentially greater concern for

feasibility of using wheat crop residue as a biomass source is that currently a significant portion

of winter wheat crop residue is already collected for competing markets such as livestock

bedding, mushroom compost, mulch, or as a fibre source for ruminant livestock.

Dedicated Biomass Crops:

In Ontario a number of species have been evaluated for dedicated biomass crops. These include:

1) perennial grass species such as switchgrass (Panicum virgatum), miscanthus (Miscanthus

spp.), big bluestem (Andropogon gerardii) and reed canary grass (Phalaris arundinacea); 2)

annual species such as hemp (Cannabis Sativa L.) and energy maize; and 3) short rotation woody

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species such as poplar (Populus trichocarpa) and willow (Salix viminalis). Perennial C4 grass

species have garnered the most attention as candidate dedicated biomass crops, particularly the

C4 species, switchgrass and miscanthus. Although they are warm season species, they are

adapted to Ontario conditions (Sage et al, 2015). They also have attributes required for

sustainable biomass crop production: perennials with a 20+ year expected stand longevity, high

yield potential (Heaton et al, 2004), low input requirements, utilize existing commercial

equipment for production (eg Figure 2 e-g), and they possess favourable greenhouse gas balances

(Eichelmann et al., 2015).

Introduction of dedicated biomass crops will almost certainly require displacement of

existing crop production since, as already mentioned, there is little to no idle land in the area

represented by Figure 1. It has been estimated that 5% of all arable land (i.e., Classes 1-5 lands)

could provide over 2 million t DM yr-1 of either switchgrass or miscanthus biomass (Kludze et

al., 2013a). Due to higher yield potential, resulting from duration of leaf area duration as well as

cold tolerance (Sage et al., 2015), a miscanthus biomass system compared with a switchgrass

biomass system would require a lower percentage of available land area to produce an equivalent

amount of biomass.

Although potential yield of switchgrass is lower, it offers other production advantages

over miscanthus. 1) Invasiveness is less of a concern since it is a native species compared to

miscanthus which has Asia as its center of origin. 2) Since it is propagated by seed it utilizes

commercially available seed based planting systems as opposed to specialized planting systems

required to plant vegetative miscanthus propagules (e.g. rhizomes see Figure 2h). 3) Also since

it is propagated by seed, cost of establishment tends to be lower and establishment success is

more consistent. 4) Switchgrass has much greater genetic diversity due to the fact it is an

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outcrossing species, compared to the limited genetic diversity of miscanthus due to vegetative

propagation systems. 5) As a result of its lower cost and more consistent establishment,

switchgrass is a better option for use on Class 4-5 land, or for use as a short-term (3-5 year)

“rotational” biomass crop on Class 1-3 land.

Both miscanthus and switchgrass are generally associated with increases in SOM and

improvements in soil health; however the magnitude of this effect is largely dependent on the

crop rotation that is being displaced (Figure 4). The role of previous cropping system on the

impacts of Miscanthus introduction on SOM was evaluated by Sanscartier et al. (2013). Life

cycle greenhouse gas (GHG) emissions were estimated for electricity generation using

Miscanthus pellets in a hypothetically retrofitted coal generating station located in Ontario. Life

cycle GHG`s, including SOM changes, were assessed for a Miscanthus production system that

displaced five contrasting cropping systems: A) maize-soybean rotation grown on Class 1-2

land, B) soybean-soybean rotation grown on Class 3 land, C) maize-forage rotation grown on

Class 3 land, D) pasture grown on Class 4-5 land, and E) a tobacco-cereal rotation grown on

Class 3-4 land. Displacement of pasture (D) or forage based rotations (C) by miscanthus had

minimal impact on SOM since pasture and forage based systems are already associated with high

levels of SOM. Also since pasture and forage production is most common on Class 4-5 soils,

and yield potential of miscanthus is lower on these soils, SOM impact was minimal. In contrast,

soybean dominated crop rotations (A or B) tend to be associated with low SOM levels, and also

occur on Class 1-3 soils that possess higher yield potential for miscanthus. Displacement of

soybean based rotations by miscanthus can significantly increase SOM and improve soil health.

Similarly since tobacco-cereal rotation are associated with low SOM, displacement by

miscanthus will result in substantial increases in SOM

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Although soil health and direct greenhouse gas benefits tend to be greatest when C4

perennial grass biomass crops are grown on Class 1-3 soil, there is concern regarding

displacement of food crops by non-food crops. This concern could be partially mitigated if

switchgrass displaced simple rotations as a short-term (3-5 years) rotational biomass crop on

Class 1-3. Use of switchgrass as a component of a rotation instead of a long term perennial

stand would mitigate many of the concerns associated with simple rotations, provide measurable

soil health benefits, and result in increases in yield of subsequent food crops in the rotation,

which could address concerns regarding food versus non-food crops. To address the food versus

non-food crop concern, there is considerable interest in producing dedicated biomass crops on

Class 4-5 land, since this would result in displacement of pastures and forages which are less

strongly perceived as food crops. However, there are other significant challenges associated

with producing biomass on Class 4-5 land (Kludze et al., 2013a). 1) Production of significant

biomass quantities would require the conversion of a relatively high percentage of the Class 4

and 5 lands compared to Class 1-3 land. 2) Availability of Class 4 and 5 lands is very region-

dependent (Figure 1) and restricting biomass production to marginal land would disadvantage the

development of biomass in regions dominated by Class1-3 land. 3) Production on marginal

lands, due to lower yield potential and scattered distribution (Figure 1) could significantly

increase production costs and transportation costs. 4) Establishment of C4 perennial grasses

would require elimination of existing pasture/forage stands; weed control during establishment

years is much easier following annual row crops than perennial forage/pasture species,

particularly since synthetic weed control options are very limited.

Conclusion

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Markets for biomass are emerging across Canada. Using Ontario as a case study, it is apparent

that private and public policies to encourage and support development of this industry must

consider the impact of source of biomass, land availability, land classification, and existing land

use patterns on economic and environmental impacts of production. Impact of crop residue

removal or introduction of dedicated biomass crops on long term system productivity and soil

health is dependent on current land use practices. Maize/soybean rotations are most vulnerable

to negative impacts of crop residue removal and removal should be encouraged from more

complex rotations. Maize/soybean rotations are also associated with potentially the greatest

benefits if displaced by a dedicated C4 perennial biomass crop. Displacement of maize/soybean

rotation by a short term (3-5yr) switchgrass stand could overcome public concerns with using

food producing land for biomass.

References

Agriculture and Agri-Food Canada. 2013. Canada Land Inventory Level-I Digital Data. [Online]

Available: http://sis.agr.gc.ca/cansis/nsdb/cli/class.html [2016 Dec. 06].

Congreves, K. A., Hayes, A., Verhallen, E. A., Van Eerd, L. L. 2015. Long-term impact of

tillage and crop rotation on soil health at four temperate agroecosystems. Soil Tillage Res.

152: 17–28.

Davis, A. S., Hill, J. D., Chase, C., Johanns, A. M., Liebman, M. 2012. Increasing Cropping

System Diversity Balances Productivity, Profitability and Environmental Health. PLoS One.

7(10). doi:10.1371/journal.pone.0047149.

Deen, W., Kataki, P. 2003. Carbon sequestration in a long-term conventional versus conservation

tillage experiment. Soil Tillage Res. 74(2): 143-150. doi:10.1016/S0167-1987(03)00162-4.

Deen, W., Martin, R. C., Hooker, D., Gaudin, A. 2016. Crop Rotation Trends: Past, Present and

Future Benefits and Drivers. Pages 35-50 in B. Ma, eds. Crop Rotations: Farming Practices,

Monitoring and Environmental Benefits. Nova Science Publications. New York, USA.

Page 13 of 21



For Review O

nly

14

Eichelmann, E., Wagner-Riddle, C., Warland, J., Deen, B., Voroney, P. 2015. Carbon dioxide

exchange dynamics over a mature switchgrass stand. GCB Bioenergy. 8: 428-442.

doi:10.1111/gcbb.12259.

Gaudin, A. C. M., Janovicek, K., Deen, B., Hooker, D. C. 2015a. Wheat improves nitrogen use

efficiency of maize and soybean-based cropping systems. Agric. Ecosyst. Environ. 210: 1-

10. doi:10.1016/j.agee.2015.04.034.

Gaudin, A. C. M., Tolhurst, T. N., Ker, A. P., Janovicek, K., Tortora, C., Martin, R. C., Deen, W.

2015b. Increasing crop diversity mitigates weather variations and improves yield stability.

PLoS One. 10(2): e0113261. doi:10.1371/journal.pone.0113261.

IPPC - Intergovernmental Panel on Climate Change. 2013. The physical science basis.

Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental

Panel on Climate Change. Cambridge, United Kingdom and New York: Cambridge

University Press. 1535 p.

Kludze, H., Deen, B., Weersink, A., van Acker, R., Janovicek, K., De Laporte, A. 2013a. Impact

of land classification on potential warm season grass biomass production in Ontario,

Canada. Can. J. Plant Sci. 93: 249-260.

Kludze, H., Deen, B., Weersink, A., van Acker, R., Janovicek, K., De Laporte, A., McDonald, I.

2013b. Estimating sustainable crop residue removal rates and costs based on soil organic

matter dynamics and rotational complexity. Biomass and Bioenergy. 56: 607-618.

Meyer-Aurich, A., Weersink, A., Janovicek, K., Deen, B. 2006a. Cost efficient rotation and

tillage options to sequester carbon and mitigate GHG emissions from agriculture in Eastern

Canada. Agric. Ecosyst. Environ. 117(2-3): 119-127. doi:10.1016/j.agee.2006.03.023.

Meyer-Aurich, A., Weersink, A., Janovicek, K., Deen, B. 2006b. Cost efficient rotation and

tillage options to sequester carbon and mitigate GHG emissions from agriculture in Eastern

Canada. Agric. Ecosyst. Environ. 117(2-3): 119-127. doi:10.1016/j.agee.2006.03.023.

Munkholm, L. J., Heck, R. J., Deen, B. 2013. Long-term rotation and tillage effects on soil

structure and crop yield. Soil Tillage Res. 127: 85-91.

Ontario Ministry of Natural Resources. 2012. Climate Change Vulnerability Assessment and

Adaptation Options for Ontario’s Clay Belt – A Case Study. [Online] Available:

http://files.ontario.ca/environment-and-energy/aquatics-climate/stdprod_100191.pdf [2016

Dec. 06].

Pittelkow, C. M., Liang, X., Linquist, B. A., van Groenigen, K. J., Lee, J., Lundy, M. E., van

Gestel, N., Six, J., Venterea, R. T., van Kessel, C. 2014. Productivity limits and potentials

of the principles of conservation agriculture. Nature. http://doi.org/10.1038/nature13809

Page 14 of 21



For Review O

nly

15

Powlson, D. S., Stirling, C. M., Jat, M. L., Gerard, B. G., Palm, C. A., Sanchez, P. A., Cassman,

K. G. 2014. Limited potential of no-till agriculture for climate change mitigation. Nat.

Clim. Chang. 4(8): 678-683. doi:10.1038/nclimate2292.

Rankin, M. 2016. Choosing between Alfalfa and Corn Silage………..or when do you trade

Medicago for Maize? [Online] Available: http://cdp.wisc.edu/jenny/crop/choosing.pdf

[2016 Dec. 06].

Richards, R. 2000. Selectable traits to increase crop photosynthesis and yield of grain crops. J.

Exp. Bot. 51: 447–458. PMID: 10938853

Sage, R. F., Peixoto, M., Friesen, P., Deen B. 2015. C4 bioenergy crops for cool climates, with

special emphasis on perennial C4 grasses. J. Exp. Bot. 66(14): 4195-4212.

doi:10.1093/jxb/erv123.

Sanscartier, D., Deen, B., Dias, G., Maclean, H. L., Dadfar, H., Mcdonald, I., Kludze, H. 2014.

Implications of land class and environmental factors on life cycle GHG emissions of

Miscanthus as a bioenergy feedstock. GCB Bioenergy. 6(4): 401-413.

doi:10.1111/gcbb.12062.

Statistics Canada, 2016. Table 001-0010 - Estimated areas, yield, production and average farm

price of principal field crops, in metric units, annually. [Online] Available:

http://www5.statcan.gc.ca/cansim/a26?lang=eng&id=10010 [2016 Dec. 06].

Tiemann, L. K., Grandy, A. S., Atkinson, E. E., Marin-Spiotta, E., McDaniel, M. D. 2015. Crop

rotational diversity enhances belowground communities and functions in an agroecosystem.

Ecol. Lett. doi:10.1111/ele.12453.

Van Eerd, L. L., Congreves, K. A., Hayes, A., Verhallen, A., Hooker, D. C. 2014. Long-term

tillage and crop rotation effects on soil quality, organic carbon, and total nitrogen. Can. J.

Soil Sci. 94(3): 303-315. doi:10.4141/cjss2013-093.

Vanhie, M., Deen, W., Lauzon, J.D., Hooker, D.C. 2015. Effect of increasing levels of maize

(Zea mays L.) residue on no-till soybean (Glycine max Merr.) in Northern production

regions: A review. Soil Tillage Res. 150: 201-210. doi:10.1016/j.still.2015.01.011.

Varvel, G. E., Wilhelm, W. W. 2008. Soil carbon levels in irrigated western Corn Belt rotations.

Agron. J. 100: 1180–1184.

Williams, A., Hunter, M. C., Kammerer, M., Kane, D. A., Jordan, N. R., Mortensen, D. A.,

Smith, R. G., Snapp, S. Davis, A. S. 2016. Soil Water Holding Capacity Mitigates

Downside Risk and Volatility in US Rainfed Maize: Time to Invest in Soil Organic Matter?

PloS One, 11(8): e0160974. http://doi.org/10.1371/journal.pone.0160974

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Table 1: Effect of SOM mineralization and formation rates on the amount of crop residue that can be annually removed from Ontario

regions while still maintaining SOM at an assumed level of 3% (Adapted from Kludze et al., 2013b)

Scenario

Assumed

Best Case

Literature

Average

Estimate

based on

Long Term

Rotation Trial

- Elora ON

Assumed

Worst Case

Mineralization Rate of Existing SOM (%) 2 2.25 2.5 2.5

Rate of SOM Formation from Residue Input

(%) 20 15 15.1 10

Region ---------------------------------- Mg yr-1 ----------------------------------

Southern Ontario 3,052,678 967,791 557,606 2,107

Western Ontario 2,240,169 757,811 459,011 4,946

Central Ontario 320,546 46,017 17,595 0

Eastern Ontario 576,720 148,183 78,784 8

Total 6,190,113 1,919,802 1,112,996 7,061

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Figure captions

Figure 1: Map of Class 1, 2, 3, 4 and 5 land in Southern (S), Western (W), Central (C), and

Eastern (E) Ontario. (Reproduced from

Kludze et al, 2013a)

Figure 2: Images of field operations for crop residue and C4 perennial grass biomass: 2a – maize

cob collection, 2b - soybean combine, 2c - maize field following grain harvest, 2d - baling

maize stover, 2e – miscanthus harvest with Kemper head, 2f – switchgrass mowing with

discbine, 2g – switchgrass baling, 2h – miscanthus rhizome.

Figure 3: Harvested areas (hectares) of major field crops shown as % of total harvested area from

1970 to 2014 for Ontario. (Source: Statistics Canada, 2016.) (Reproduced from Deen et al.,

2016)

Figure 4: Life cycle Greenhouse Gas (GHG) emissions for the five crop rotation scenarios

displaced by Miscanthus per oven dry tonne of Miscanthus bale (ODTbale) at the farm gate.

Negative “Change in carbon (C) pools” corresponds to a net uptake of carbon to the system.

A, B, C D, E represent five contrasting crop rotation displacement scenarios: A maize-soy,

Class 1-2 land; B soy-soy, Class 3 land; C maize-forage, Class 3 land; D pasture, Class 4-

5 land; E tobacco-cereal, Class 3-4 land. (Reproduced from Sanscartier et al., 2013)

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2d2c2a 2b

2e 2f 2g 2h

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0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

1970

1972

1974

1976

1978

1980

1982

1984

1986

1988

1990

1992

1994

1996

1998

2000

2002

2004

2006

2008

2010

2012

2014

Soybeans

Winter wheat

Spring cereals

Misc

Tame hay

Corn (grain, silage)

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-350

-250

-150

-50

50

150

250

A B C D E

GH

G e

mis

sion

s (k

g C

O2e

q/O

DT

bale)

Change in C pools

Soil Nitrous Oxide

Fertilizer production

All farm activities exceptfertilizer productionEstablishment andterminationNet emissions

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