9. 9
Figure 5: Agricultural greenhouse gas emissions mitigation logic model
Category Sub‐category Intervention options Risks, limitations & co‐benefits
Reduce demand for carbon
intensive agricultural
commodities
• Reduce per capita meat
consumption
• Reduce % of food waste
• Vegetarianism campaign
• Food service campaign
• Change in expiration date
protocols
• Solutions difficult to scale
• Difficult to develop mandates or
incentives
Reduce agricultural
commodity production
• Afforestation
• Restoration of wetlands, organic
soils
• Convert land to set‐asides or
buffers
• Production tax
• Expand CRP
• No grazing on fed lands
• Stricter CWA regulations
• Decrease commodity subsidies
• End biofuels subsidies
• Pay farmers not to farm
• Leakage: Although these
measures will reduce emissions
regionally or nationally, without
a simultaneous shift in demand,
production will likely just shift
elsewhere, possibly to a less
carbon efficient location.
Shift production to less
greenhouse gas intensive
commodities
• Use more perennials
• Increase production of woody
crops, agroforestry
• Convert cropland to pastureland
• Diversify crop rotation
• Subsidize the lowest
greenhouse gas crops
• Revenue neutral tax on top
greenhouse gas agricultural
products (e.g. dairy and corn)
• May also be a risk of leakage
with these interventions. The
dynamics of specific changes in
production patterns would need
to be modeled.
Change practices to reduce
greenhouse gas intensity of
production
• Improve productivity and
management of grazed lands
• Improve productivity and
management of croplands (e.g.
tillage, cover crops, nutrient use
efficiency)
• Improve livestock efficiency
• Improved manure management
• USDA programs
• Supply chain pressure
• Carbon markets
• Other PES markets
• Some of the practices in this
category may increase intensity
(positive leakage effects) and/or
have positive environmental co‐
benefits.
• Some may have negative
impacts on other environmental
resources (e.g. water, toxics).
12. 12
Take “leaky” land out of production ‐ Cropland that is most susceptible to nitrogen loss can be
taken out of production. The risk here is that this land may be highly productive, so not a good
choice for set‐asides.
Shift production to less nitrogen intensive commodities ‐ Cropping patterns could shift to less
nitrogen intensive crops. Depending on the level of intervention necessary, this approach could
lead to indirect land use change and a rise in net greenhouse gas emissions. However, some
studies suggest that just a small amount of perennials integrated into major crops can have a
significant impact on nitrogen losses.
Reduce the nitrogen intensity of production ‐ Nitrogen losses could be decreased by enhancing
the efficiency of fertilizer use. This approach is promising because it does not require a change in
production patterns and in many cases should lead to economic gains for the producers.
However, it requires a behavioral change which may be difficult to scale quickly.
Adoption of conservation practices ‐ Nitrogen losses could be decreased through an increased
use of conservation practices that filter nitrogen (e.g., buffer strips, tile bioreactors, wetlands,
grassed waterways). These practices can be very effective at reducing nitrogen losses, but are
generally not economically advantageous to the producers and require voluntary actions by a
large number of actors.
Progress to date
The last two approaches, increasing nutrient use efficiency through best management practices for
fertilizer management and increasing the use of conservation measures that filter nitrogen, are
commonly championed by conservation groups, and supported by a number of USDA programs. Efforts
to date have achieved some success in reducing nitrogen losses, but there is still plenty of room for
further improvement.
The USDA’s Conservation Effects Assessment Project (CEAP) studied the impact of voluntary adoption of
conservation measures by producers across the US from 2003‐2006 in the Upper Mississippi River Basin,
the Great Lakes Region, and the Chesapeake Bay. The CEAP found that nitrogen losses have been
reduced by 18‐29% during these years, with result varying by region. It further determined that
additional reductions of 27‐41% are possible by increasing the level of treatment, particularly to acres
that are the most vulnerable to nitrogen losses.
There is likewise a great opportunity to reduce nitrogen losses through increased nutrient use efficiency
with respect to fertilizer application. Many producers apply more fertilizer than is necessary for crop
growth thanks to a combination of two primary factors: 1) it is a low‐cost way to hedge against the risk
of low yields, and 2) the information provided by extension agents and crop advisors is often not
tailored to specific sites so producers lack sufficient information to manage fertilizers in an adaptive and
precise manner. A recent study by the USDA’s Economic Research Service finds that a majority of acres
planted in major commodity crops do not adhere to best management practices, as defined by the
USDA, leading to hundreds of thousands of tons of excess nitrogen application, primarily concentrated
in the Midwest. The study further found that some of the most vulnerable land, tile drained land in the
14. 14
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