life cycle analysis – Livestock and Poultry Environmental Learning Community

Purpose

The goal of the Sustainable Dairy “Virtual Farm” website is to disseminate research-based information to diverse audiences from one platform. This is done with layers of information starting with the m

ost basic then drilling down to peer-reviewed publications, data from life-cycle assessment studies and models related to the topics. The Virtual Farm focuses on decision makers and stakeholders including consumers, producers, policymakers, scientists and students who are interested in milk production on modern dairy farms. The top entry level of the site navigates through agricultural topics of interest to the general public. Producers can navigate to a middle level to learn about practices and how they might help them continue to produce milk for consumers responsibly in a changing climate while maintaining profitability. Featured beneficial (best) management practices (BMPs) reflect options related to dairy sustainability, climate change, greenhouse gas emissions, and milk production. Researchers can navigate directly to deeper levels to publications, tools, models, and scientific data. The website is designed to encourage users to dig deeper and discover more detailed information as their interest develops related to sustainable dairies and the environment.

What did we do?

As part of a USDA Dairy Coordinated Agricultural Project addressing climate change issues in the Great Lakes region, this online platform was developed to house various products of the transdisciplinary project in an accessible learning site. The Virtual Farm provides information about issues surrounding milk production, sustainability, and farm-related greenhouse gases. The web interface features a user-friendly, visually-appealing interactive “virtual farm” that explains these issues starting at a less-technical level, while also leading to much deeper research into each area. The idea behind this was to engage a general audience, then encourage them to dig deeper into the website for more technical information via Extension offerings.

The main landing page shows two sizes of dairy farms: 150 and 1,500-cows. The primary concept was to replace an all-day tour of multiple real dairy farms by combining their features into one ‘virtual farm’. For example, the virtual farm can describe and demonstrate the impact of various manure processing technologies. Users can explore the layout image, hover over labeled features for a brief description, and click to learn more about five main categories: crops and soils, manure management, milk production, herd management, and feed management. Each category page contains a narrative overview with illustrations and links to more detailed information.

What have we learned?

The primary benefit is that participants can learn about different practices, at their level of interest, all in one place. The virtual farm incorporates a broad theme of sustainability targeted at farming operations in the northeastern Great Lakes region of the USA.

The project has included regional differences in dairy farming practices and some important reasons for this such as environmental concerns (focus on N and/or P management in different watersheds) and long-term climate projections. Dairy industry supporters find value in having a one-stop repository of information on overall sustainability topics rather than having to visit various organizations’ sites.

Acknowledgements

This material is based upon work that is supported by the National Institute of Food and Agriculture, U.S. Department of Agriculture, under award number 2013-68002-20525. Any opinions, findings, conclusions or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture.

The authors are solely responsible for the content of these proceedings. The technical information does not necessarily reflect the official position of the sponsoring agencies or institutions represented by planning committee members, and inclusion and distribution herein does not constitute an endorsement of views expressed by the same. Printed materials included herein are not refereed publications. Citations should appear as follows. EXAMPLE: Authors. 2017. Title of presentation. Waste to Worth: Spreading Science and Solutions. Cary, NC. April 18-21, 2017. URL of this page. Accessed on: today’s date.

A carbon footprint is a total of all the greenhouse gas emissions (GHG) from a process or industry. A life cycle assessment (LCA) is the process used to figure out what GHG emissions will be included in the footprint. More technically, it is systematic way of looking at a product’s complete life cycle and calculating a “footprint”. In addition to carbon footprints, there are efforts to calculate land, water, and other environmental footprints.

Below are highlights from several different reports that looked at the carbon footprint of the pork industry on a national and international scale. A comparison between different ways to raise pigs was also highlighted.

Snapshot of the Present Time

On a national scale, a report on the National Life Cycle Carbon Footprint Study for Production of Swine in the U.S. was conducted and published in 2011.

The report concluded that the carbon footprint to prepare and consume a 4 oz serving of pork was ~2.5 lbs of carbon dioxide equivalents. Figure 1 (below) from that report shows the relative breakdown of the industry’s estimated greenhouse gas emissions:

Live animal production made up 62.1% of the emissions. That is further broken down and presented in second column (right).
Processing – 5.6%
Retail – 7.54%
Consumption – 23.5% including refrigeration, cooking, and methane from food waste in landfill
Packaging (1.3%);

Life cycle assessment of pork production in the U.S.

Comparison Over 50 Years of Production

Another example of an industry-wide analysis, this one comparing over time, is a “50-year comparison of the carbon footprint of the U.S. swine herd 1959 – 2009” (29 pp; PDF). The pork industry overall emits more total greenhouse gases than 50 years ago, but actually emits much less per pound of pork produced because of improvements in efficiency.

From that publication:

The U.S. swine industry produces pigs far more efficiently today (2009) than in 1959. The number of hogs marketed has increased 29% (87.6 million in 1959 to 112.6 million in 2009 after removing market hogs imported directly to harvest) from a breeding herd that is 39% smaller. The efficiency gain is even more impressive when measured against the total dressed carcass weight harvested. Dressed carcass yield leaving the farm has nearly doubled in 50 years from 12.1 billion pounds to 22.8 billion pounds. This increase in productivity has resulted in an increase of 2,231 pounds (2.5x) of carcass harvested annually per sow – year. Today, it takes only five hogs (breeding and market) to produce the same amount of pork that required eight hogs in 1959.

Comparing Different Ways of Raising Pigs

An example of an LCA that looks at different types of systems is “Life-cycle assessment of commodity and niche swine operations“. (informal Q&A and journal article both available). From the journal article (bottom of page 5):

High-profitability operations have consistently lower impacts compared to low-profitability operations for both commodity and deep-bedded niche piglet production.

Global Assessment from Backyard to Industrial Systems

On an international scale, the report “Greenhouse gas emissions from pig and chicken supply chains” was published in 2013. This study looked at all scales of farms from backyard pigs to industrial production (large confinement operations). Over the entire scale, they estimated that the carbon footprint of pork for every kg (~2.2 lbs) of pig carcass weight has an emissions intensity of 6.1 kg of carbon dioxide equivalent.

This report found that backyard systems, especially in some parts of the world, have low emissions, largely due to by-product or “second-grade” feeds. Industrial pig systems tended to have more emissions intensity than backyard systems, with the emissions from liquid/slurry manure management systems being a big reason. From the conclusion of the report:

When drawing any conclusions about scope for improvement, the following points should be borne in mind: (a)differences in emission intensity may reflect differences in production systems that have arisen over time to enable the system to perform better within a given context, e.g. to make them more profitable, or resilient; (b) focusing on a single measure of efficiency (in this case GHG emissions per kg of output) can lead to positive and negative side effects on, for instance, biodiversity, water quality and animal welfare; (c) reducing GHG emissions is not the only objective producers need to satisfy, as they also need to respond to changing economic and physical conditions.

How Do Carbon Footprints Compare?

It is very important to note that when looking at data and numbers generated from different reports like these, the carbon footprints are difficult to compare unless they use the same LCA. Presenting carbon footprints from different LCA’s is an “apples to oranges” comparison. Only when the same LCA is used, can they be an “apples to apples” comparison.

Additional Information

Pig Production Environmental Footprint Calculator
[Fact sheet] What is a carbon footprint?
[Archived webinar] Life Cycle Assessment Modeling for the Pork Industry (Note: the audio of the recording is not great quality – we apologize for those issues)
What greenhouse gases are emitted by pig farms?
Evaluating the environmental footprint of the pork industry

Acknowledgements

Authors: Amy Carroll, University of Arkansas and Jill Heemstra, University of Nebraska jheemstra@unl.edu

This information is part of the program “Integrated Resource Management Tool to Mitigate the Carbon Footprint of Swine Produced In the U.S.,” and is supported by Agriculture and Food Research Initiative Competitive Grant no. 2011-68002-30208 from the USDA National Institute of Food and Agriculture. Project website.