According to some early findings from a study by Penn State graduate student Erica Rogers, poultry producers are potentially lowering their impact on the Chesapeake Bay.
Rogers and fellow Penn State graduate student Amy Barkley discussed those initial findings from their two master’s thesis projects with the poultry service technicians attending Monday’s Penn State Poultry Health and Management Seminar at the Lancaster Farm and Home Center.
Her project’s goal is to accurately depict poultry’s contribution to the Chesapeake Bay Total Maximum Daily Load. The Chesapeake Bay “is one of the most studied watersheds in the world,” she said, but the problem with the current model is “they are using outdated information for poultry.”
Rogers built her work around the concept that poultry litter management has changed and farmers have adopted more precise diets for their flocks. READ MORE
The simple answer is it depends on many factors. While not exactly a satisfying answer to a complex scenario, it truly depends on the manure handling system, cropping system, field conditions, weather forecasts, time and labor available, volume of manure in the pit and many more factors. What is the right decision when there are so many factors out of our control? The best answer is to know the risk factors during the time of manure application and minimize those risks while optimizing crop production with those additional manure nutrients.
To help solve this complex scenario, a new tool is available for Michigan livestock producers to use when making decisions on when and where to spread manure. The Michigan State University EnviroImpact Tool is part of the Michigan Manure Management Advisory System that was been developed through a partnership between National Weather Service/NOAA, Michigan Department of Agriculture and Rural Development (MDARD), Michigan Agriculture Environmental Assurance Program (MAEAP), Michigan State University (MSU) Institute of Water Research, Michigan Sea Grant and Michigan State University Extension. The MSU EnviroImpact Tool provides maps showing short-term runoff risks for daily manure application planning purposes; taking into account factors including precipitation, temperature, soil moisture and landscape characteristics. Anyone handling and applying livestock manure in Michigan can use this tool to determine how risky it will be spread manure on their fields.
Key features of this tool include:
- Ability to sign up for e-mail or text message alerts specific to your field locations for high-risk runoff days.
- Easy visualization of the short-term risk of manure runoff.
- Ability to zoom in on the map to your field(s) and click on the location to determine the potential risk of runoff from manure application.
- Capability to login to the tool to draw and save your fields on the map to determine risk of runoff at any time.
- Automatic daily runoff risk forecast updates from the National Weather Service.
- Access to additional resources on manure management.
Additional Manure Application Considerations:
Risk increases with soil moisture. If you know that your fields are particularly wet, you should know that the risk of runoff from your fields would be higher than what is shown on the risk map. The opposite may hold true if you estimate that your soil moisture values are lower.
Even if the map shows low risk of runoff, your fields may not be dry enough to spread manure. Applying liquid manure (typically equivalent to 1/3 to 1 inch or more of rainfall) to wet fields could lead to a direct manure runoff, even if the field is otherwise a low risk site due to low slope, etc. Make sure your fields are dry enough to accept additional moisture. Additionally, operating field equipment on wet fields could lead to soil compaction.
Liquid manure applications increase soil moisture. An application of 27,000 gallons per acre of liquid manure is the equivalent of adding approximately 1 inch of water to your fields. A liquid manure application effectively increases your soil moisture, and therefore the risk of runoff from fields receiving liquid manure could be higher than what is shown on the risk map.
Snow-covered and frozen fields are high risk. If you have snow on your fields, the risk of runoff from your fields could be higher especially if spreading manure in the later winter months of February or March (due to snowmelt or rainfall).
Some fields are always higher risk areas. These are areas of concern on your farm, and might include fields with higher slopes, tighter soils (clay), poor drainage or close to sensitive areas such as surface waters, etc. Many of these areas should be identified in your Manure Management Plan and/or sensitive area maps. Use caution when applying manure in these areas, regardless of what the risk map indicates.
Livestock producers and manure applicators should contact their local Conservation District MAEAP technician for help in developing a Manure Management Plan that takes into account a manure-spreading plan, sensitive area field maps and alternatives to spreading if necessary. Another great resource for making manure application decisions is MDARD's Right to Farm Generally Accepted Agricultural Management Practices (GAAMPs) specific to Manure Management and Utilization.
In recent years, scientists around the world have made great progress in their attempts to recycle cattle manure, including turning it into natural fertilizer and biogas, but Eindhoven designer, Jalila Essaïdi didn't think they were efficient enough to solve the global manure surplus problem.
So, she started on her very own solution, one that approached animal waste as a valuable material that could be processed into useful products. The results of her work prove that manure really is worth its weight in gold.
Working in her BioArtLab, Essaïdi discovered that cow manure provided both the base for a new, bio-degradable material and the chemicals required to produce it.
She started by separating the waste, with the dry manure used to extract pure cellulose from the grass that cows eat. From the wet manure, she extracted acids used to create cellulose acetate, a natural liquid plastic. This was used to make fibers, which are later turned into fabric or bio-plastics, but it can also be freeze-dried to create an aerogel.
The new material was named Mestic, from mest, the Dutch word for manure. Essaïdi claims that it has the same properties as plastic derived from fossil fuels, but is bio-degradable. Better yet, the degradability can be tweaked in the lab, making it possible to create materials that last for different periods of time depending on their purpose. READ MORE
The three projects with the university are supported by the $27 million Agricultural Greenhouse Gases Program (AGGP), to help the Canadian farming sector become a world leader in the development and use of clean and sustainable agricultural technologies and practices. These projects will also help farmers increase their understanding of GHG emissions.
The AGGP covers four priority areas of research: livestock systems, cropping systems, agricultural water use efficiency and agro-forestry.
"This is a significant investment in U of G research, innovation, and knowledge mobilization. All three of these projects will help improve life and protect our planet, from improving agroforestry practices, to developing crop fertilization methods that reduce emissions, to use of aerial devices to assess soil carbon levels and elevate precision agriculture," said Malcolm Campbell, Vice-President (research), University of Guelph
The new AGGP investments will continue to support the work of the Global Research Alliance on Agricultural Greenhouse Gases, which brings together 47 countries to find ways to grow more food without growing greenhouse gas emissions. READ MORE
The Environmental Integrity Project analyzed hundreds of state records for the report released Wednesday. In addition to E. coli, which can sicken the swimmers, fishermen and tubers who flock to the river, the report also found elevated levels of phosphorous, which contributes to the growth of algae blooms and low-oxygen "dead zones." READ MORE
Tasked with helping Nebraska Public Power District (NPPD) turn biogas into a more-refined form of natural gas, the team of Meryl Bloomfield, Heather Newell, K.J. Hafer and Dave Hansen saw that the state was among the nation's leaders in not only cattle population but in manure production.
Using an anaerobic digestion process, the team proposes turning that manure not only into fertilizer for crops but natural gas that NPPD could also use to create electricity that powers farms and rural communities across the state.
"Compared to other renewable energy sources – like wind and solar – biogas is more consistent," said Bloomfield. "Cows are always going to produce manure. You don't have to rely on having a sunny day or a windy day, especially In Nebraska, where wind and solar plants might not be as reliable as in Arizona and California."
According to The Cattle Network, Nebraska ranked second nationally in 2015 with approximately 6.3 million cattle or about seven percent of the U.S. population. One of the biggest uses of the manure produced by the cattle is the production of fertilizer.
The student team worked to develop a method that would allow the production of natural gas and still maintain a viable supply for fertilizer production. But that led to it expanding on its goal by proposing a solution that could be an economic boost to the rural community – a biogas upgrade refinery that would be strategically located near Broken Bow.
The refined natural gas from the Nebraska Biogas Upgrading Refinery would then be piped to NPPD's Canaday Station southeast of Lexington, where it could be used to create electricity.
"It would be centralized to where the cows are," Hansen said. "After designing the plant, we determined we'd need about a quarter of a million head of cattle to achieve the manure supply sufficient to reach the capacity NPPD is looking for.
The natural gas that would be similar to the gas used in homes across the country, Hansen said, except it would be collected as part of a natural process rather than relying on traditional means of extracting the gas – such as fracking or refining fossil fuels.
Newell also said the process would be more beneficial to the ecology.
"In doing this, we're reducing greenhouse gases from the cow manure that sits out and naturally becomes fertilizer," Newell said. "We're reducing the carbon dioxide and creating something useful from it."
Though their proposal isn't guaranteed to be implemented, Bloomfield said thinking about the human impact made this senior capstone experience valuable for the entire team.
"Knowing that it could be even a stepping stone to something for NPPD changed how we approached it," Bloomfield said. "When you're thinking theoretically, you can go a lot of different directions. When you're thinking about how it affects people and their lives, that's when it gets real."
"Livestock are significant emission contributors," says Dr. Sean McGinn of Agriculture and Agri-Food Canada, a long-time researcher in the emissions area. "That's quite clear and generally recognized by the agricultural research community."
Fifty to 60 percent of feed nitrogen is lost as ammonia at the feedlot. Eight to 10 percent of Canada's greenhouse gas emissions are from agriculture and 90 percent of the atmospheric ammonia comes from cattle manure. Ammonia in the atmosphere is an economic loss because the nitrogen fertilizer potential of manure is lowered. And it's a health hazard. Ammonia mixes with acid to form fine aerosols, the white haze seen in confined airsheds.
"We know beef feedlots are 'hot spots' of ammonia emissions on the landscape, but we didn't know as much about the dynamics of ammonia emissions from feedlots. For example we didn't have real numbers from actual feedlots on how much is emitted, how much is deposited on nearby soil and how much re-emission occurs when that happens."
That's what McGinn and his colleague Dr. Tom Flesch (University of Alberta) set out to understand. Backed by funding from the Alberta Livestock and Meat Agency (ALMA), a two-year project investigated the fate of nitrogen in feedlots, what amount is deposited on land downwind and how much is carried long distances.
The other part of their research involves measuring methane and nitrous oxide, two prominent greenhouse gasses. Methane is produced by cattle due to the anaerobic digestion of feed in the cow's rumen and both nitrous oxide and methane come from stored manure in the pens.
The research produced significant results on several fronts from techniques to measure on a commercial scale, to new information on transfer, deposits and re-emission to nearby lands, to related opportunities for mitigation and management.
New measuring techniques
One major positive outcome was the development of new measuring technology adapted from what has been used successfully for measuring flare emissions in the oil and gas industry.
Using open path lasers that move over the feedlot and calculate concentration and wind characteristics, the system is able to measure emissions regardless of wind direction.
Measuring in real world situations offers some significant advantages to the more standard research protocols of using animals in individual chambers to measure emissions, says McGinn.
This new technique evaluates the feedlot as a whole, which means it can consider whole-unit management aspects which impact emissions. Also, by keeping animals in their natural environment and not interfering with them in any way, the laser approach promises more accurate, commercial scale results.
On a bigger picture level, this means actual feedlot emission numbers can be used in greenhouse gas assessments, an improvement from past practices of using estimates from global sources.
Early results show surprises
One of the surprises learned from this study was the fact that a significant fraction of ammonia was deposited on the land adjacent to the feedlot and, once deposited, how much was reemitted into the atmosphere.
"Our results illustrate the dynamics of reactive ammonia in the vicinity of a beef cattle feedlot," says McGinn. "It confirmed that a large portion of the nitrogen fed as crude protein is volatized from the feedlot's cattle manure. In the local vicinity of a feedlot, both ammonia deposition (14 percent of the emitted ammonia) and reemission occurred. That 14 percent is a large amount considering a typical feedlot emits one to two tonnes of ammonia per day."
There was a change in the soil captured ammonia that decreased with distance from the feedlot (50 percent over 200 m).
Logically it follows that quantifying the local dry ammonia deposition to surrounding fields is required when applying feedlot-based emissions to a large-scale emissions inventory, says McGinn. Failure to do that could mean badly misrepresenting the real situation.
"We need better emissions numbers to anchor effective public policy and fairly represent the feedlot industry in that data pool," says McGinn. "It's important to have research done before policy is set. The U.S. cattle feeding industry already has specific ammonia emission targets in place."
Related scientific paper here: "Ammonia Emission from a Beef Cattle Feedlot and Its Dry Local Deposition and Re-Emission."
Now scientists at the Department of Energy's Pacific Northwest National Laboratory (PNNL) have developed a new system to convert methane into a deep green, energy-rich, gelatin-like substance that can be used as the basis for biofuels and other bioproducts, specialty chemicals — and even feed for cows that create the gas in the first place.
"We take a waste product that is normally an expense and upgrade it to microbial biomass which can be used to make fuel, fertilizer, animal feed, chemicals and other products," said Hans Bernstein, corresponding author of a recent paper in Bioresource Technology.
Methane is an unavoidable byproduct of our lifestyle. Manure from dairy cows, cattle and other livestock that provide us food often breaks down into methane. Drilling processes used to obtain the oil and natural gas we use to drive our cars and trucks or heat our homes often vent or burn off excess methane to the atmosphere, wasting an important energy resourcePNNL scientists approached the problem by getting two very different micro-organisms to live together in harmony.
One is a methane-loving methanotroph, found underground near rice paddies and landfills — where natural methane production typically occurs. The other is a photosynthetic cyanobacterium that resembles algae. Originally cultured from a lake in Siberia, it uses light along with carbon dioxide to produce oxygen.
The two aren't usually found together, but the two co-exist in harmony in a bioreactor at PNNL — thanks to a co-culture system created by Leo Kucek, Grigoriy E. Pinchuk, and Sergey Stolyar as well as Eric Hill and Alex Beliaev, who are two authors of the current paper.
PNNL scientist Hans Bernstein collected methane gas from a Washington dairy farm and Colorado oil fields and fed it to the microbes in the bioreactor.
One bacterium, Methylomicrobium alcaliphilum 20Z, ate the methane and produced carbon dioxide and energy-rich biomass made up largely of a form of carbon that can be used to produce energy.
But Methylomicrobium alcaliphilum 20Z can't do it alone. It needs the other micro-organism, Synechococcus species 7002, which uses light to produce the steady stream of oxygen its counterpart needs to carry out the methane-consuming reaction.
Each one accomplishes an important task while supplying the other with a substance it needs to survive. They keep each other happy and well fed — as Bernstein puts it, they're engaging in a "productive metabolic coupling." READ MORE
Runoff from agricultural sites can be an important source of phosphorus pollution. To help evaluate and reduce this risk, the U.S. Department of Agriculture (USDA) first proposed a phosphorus index concept in the early 1990s.
Since then, science progressed and methods improved. In New York State, scientists and agency staff developed and released a phosphorus index in 2003. Now, a new project proposes a restructured index to build on phosphorus management efforts in that state and beyond.
"The idea is to account for the characteristics of a field, and help evaluate the risk of phosphorus runoff from that location," says Quirine Ketterings, lead author of the new study.
The new index structure improves upon previous approaches. It focuses on the existing risk of phosphorus runoff from a field based on the location and how it is currently managed. Qualities like ground cover, erosion potential, and distance to a stream or water-body all come into play. The index also highlights best management practices to reduce this risk.
"The new index approach will direct farmers toward an increasingly safer series of practices," says Ketterings. "Higher-risk fields require more and safer practices to reduce and manage phosphorus runoff."
Ketterings directs the nutrient management spear program at Cornell University. She and her colleagues used a combination of surveys, computer-generated examples, and old-fashioned number crunching. They used characteristics of thousands of farm fields to develop the new index. Involving farmers and farm advisors was also a key step.
"As stakeholders, farmers and farm advisors are more likely to make changes if they understand why," says Ketterings. "Plus, they have experience and knowledge that folks in academia and in governmental agencies often do not."
This field experience can be vital. "Involving stakeholders in decision-making and getting their feedback makes the final product more workable," says Ketterings. "It may also prevent mistakes that limit implementation and effectiveness."
Ketterings stresses that the previous index was not wrong.
"Farming is a business of continuous improvement and so is science," she says. "The initial index was based on the best scientific understanding available at that time. Our new index builds and improves upon the experience and scientific knowledge we have accumulated since the first index was implemented. It is likely this new index will be updated in the future as our knowledge evolves."
The previous index approach could be somewhat time-consuming for planners, according to Ketterings. Further, it didn't always help identify the most effective practices for farmers. The new approach addresses both of these issues.
"We wanted the new index to be practical to use," she says. "The best index has no value if people cannot or will not implement it."
In some circumstances of low or medium soil test phosphorus, the original New York state phosphorus index allowed farms to apply manure and fertilizer in what we now consider to be potentially high-risk settings.
"The new index approach proposes soil test phosphorus cutoffs and also encourages placing manure below the soil surface," says Ketterings. "These changes will bring improvements in phosphorus utilization and management across the farm."
Ketterings also thinks that the new index is more intuitive.
"It allows for ranking of fields based on their inherent risk of phosphorus transport if manure was applied," she says. "It really emphasizes implementing best management practices to reduce phosphorus losses from fields."
In addition, the proposed index approach could make it easier to develop similar indices across state lines, according to Ketterings. This makes sense, since watersheds don't follow state boundaries. Growers could use different practices, if deemed appropriate, for different regions.
READ MORE about Ketterings' work in Journal of Environmental Quality.
A mobile system for removing phosphorus from cow manure may offer dairy farmers greater flexibility in where, when, and how they use the nutrient to fertilize crops.
The idea behind the Manure Phosphorus Extraction System (MAPHEX) is to remove phosphorus and concentrate it in a form easier to manage, says Clinton Church, an Agricultural Research Service (ARS) environmental chemist.
“Some farmers with plenty of land may need to drive 20 miles or more to reach some fields,” says Church. “That makes transporting large volumes of manure uneconomical (or impractical), even if the crops there need phosphorus.”
Working with Pennsylvania State University collaborators, Church and his colleagues developed and tested MAPHEX as a way farmers could “mine” phosphorus from their manure and market it as a value-added product.
To do this, the team mounted an auger press, centrifuge, vacuum-filter unit, and other components atop two trailer beds so the entire system could be driven to a farm and operated onsite on a daily or rotational basis.
MAPHEX works in three stages, each removing progressively smaller fiber particles and other phosphorus-containing matter from the manure. In addition, there is a chemical treatment step between the last two stages to convert dissolved phosphorus into a filterable particle. Water extracted from the manure is retained on the farm; it contains most of the manure’s nitrogen.
MAPHEX works quickly. In about 10 minutes, it can extract 99 percent of the phosphorus from 250 gallons of manure. Additionally, it removes odor from the manure.
The fiber and other phosphorus-containing particles exit the system as concentrated solids, which can be transported for use off-farm or sold to nurseries. Solids from MAPHEX’s first treatment stage could also be sold as cow bedding.
The MAPHEX team will begin demonstrating a full-scale version of its system on a working dairy farm this spring.
Jan Suszkiw is with the U.S. Department of Agriculture’s Agriculture Research Service office.
February 23, 2017, Green Bay, WI – In a new study of groundwater conditions in dairy farm-intensive Kewaunee County, researchers found higher levels of well contamination from cattle during wet weather events — when manure, rain and melting snow can seep quickly into the ground.
But the results also show that cattle in this northeastern county are not the only source of tainted drinking water. Human waste from sanitary systems is also polluting wells. READ MORE
February 21, 2017 – Livestock farmers face many challenges. One of the most daunting is deciding where to apply manure during the winter months.
Rumors and fears about winter spreading bans have been circulating for years. The major concern with winter application of manure is losing manure nutrients in surface runoff from fields. Michigan State University Extension encourages farmers to be aware of different tools and practices that can minimize potentially negative effects associated with winter manure application, especially those that farm in priority watersheds such as the Western Lake Erie Basin and Saginaw Bay watersheds.
A conservation practice that farmers can implement to minimize manure runoff while capturing manure nutrients is to spread on fields that have a cover crop. Cover crops can capture and hold onto the manure so that it is less likely to leave the field. This practice may decrease the risk of manure nutrients running off into surface waters or leaching through field tiles. Cover crops can uptake the manure nutrients in the spring for an early growth. This not only means healthier plants but it also decreases the likelihood of nitrogen leaching through the soil and getting into groundwater. Another benefit may be an increase in biomass production, which equates to an increase in organic matter. Cover crops can improve soil health and less fertilizer may be needed for crop production.
If you would like to learn more about cover crops, the Midwest Cover Crops Council (MCCC) is holding its annual business meeting followed by a one-day conference this year in Michigan. The MCCC conference will be held on March 15, 2017 at the Crowne Plaza 5700 28th Street SE. Grand Rapids, MI 49546. The MCCC business meeting will precede the conference on March 14. This event is an opportunity for farmers, researchers, educators, agency personnel, NGOs and agribusiness to learn from one another about the latest information in successful cover cropping. Michigan State University Extension is hosting the meeting and conference. The theme of this year’s conference is “Making Cover Crops Work – Experiences from the Field.” In addition to joint sessions on cover crop termination and inter-seeding of cover crops, three concurrent sessions will feature cover crop use in field crops, vegetable crops and forage/grazing systems. CCA and RUP credits are pending. Exhibitors providing cover crop and other ag-related services will be present. Register on the MCCC annual meeting page.
A new tool is in the toolbox for Michigan livestock producers to use when making decisions on when and where to spread manure. The MSU EnviroImpact Tool is part of the Michigan Manure Management Advisory System that was been developed through a partnership between National Weather Service/NOAA, Michigan Department of Agriculture and Rural Development (MDARD), Michigan Agriculture Environmental Assurance Program (MAEAP), Michigan State University (MSU) Institute of Water Research, Michigan Sea Grant and MSU Extension. The MSU EnviroImpact Tool provides maps showing short-term runoff risks for daily manure application planning purposes; taking into account factors including precipitation, temperature, soil moisture and landscape characteristics. Anyone that is handling and applying livestock manure in Michigan can use this tool to determine how risky it will be spread manure on his/her fields.
January 30, 2017, Madison, WI – Wisconsin is known as America's dairy land – more than one-third of all the cows in America live on some 3,000 farms in the state. Those bovine residents contribute to a thriving dairy industry, but milk is not the only thing that they produce in prodigious quantities. That many cows inevitably leads to a significant amount of manure, and managing that organic waste is an important problem for everyone living in the state.
"It is a horribly complex problem and we all contribute to it and are affected by it," says Victor Zavala, the Richard H. Soit assistant professor in chemical and biological engineering at the University of Wisconsin-Madison. "Farms generate the manure and we are all affected by its environmental impacts. But manure production is driven by strong economic forces originating from urban areas that demand dairy products."
Phosphorus runoff from manure causes algal blooms in water bodies. Manure also releases pathogenic bacteria and methane gas. Technologies do exist to process organic waste, while at the same time recovering valuable products such as biogas and struvite for fertilizer; but these technologies are expensive and affordable only for large farms.
Yet, deciding on a suitable solution involves much more than technology cost alone: Where to locate manure processing plants, how to transport the waste, and who should pay for the equipment are all challenging questions. With so many competing interests, no single individual can realistically keep track of all the costs, benefits, and constraints.
"This problem is too complex. You need to find simpler and more direct ways to explain the interactions between social, economic and technology aspects to people making decisions," says Zavala.
Conflicting stakeholder interests complicate the problem further; most of the time such conflicts arise unnecessarily because of a lack of data about technology and logistical constraints.
A decision-making framework can help people to better grasp the large number of factors that need to be considered and to narrow down the options to a few potential solutions – and Zavala and his colleagues are developing such a framework to help people reach agreements in complex and potentially controversial decisions such as manure management. By systematically quantifying costs, environmental impacts, and people's opinions and priorities, these tools can help lead to compromise solutions that maximize collective stakeholder satisfaction.
With support from the U.S. Department of Agriculture, the National Science Foundation, the U.S. Environmental Protection Agency, and Dane County in Wisconsin, Zavala is creating decision-making frameworks that government and industry can use to identify optimal strategies to tackle the manure management problem.
"We are hoping that with this framework, we can have a more informed negotiation process. Instead of just telling stakeholders what they should do, we want to provide better frameworks for people to negotiate on what the manure management infrastructure would do," says Zavala, who is leading the effort along with Rebecca Larson, an assistant professor of biological and systems engineering at UW-Madison.
Importantly, the researchers will include quantitative measures of stakeholders' satisfaction in their models to ensure that the opinions of all groups – rural and urban communities, farmers, politicians, environmental regulators, and scientists alike – are heard and considered.
"We try to come up with fair solutions that please as many stakeholders as possible, with the important observation that you will very rarely be able to please everyone," says Zavala. "The framework can also be used to inform stakeholders on how their opinions influence (or not) the final decision. That is a powerful piece of information."
In related research, Zavala and colleagues recently completed a project on organic waste management in Dane County, WI. That team included UW-Madison/UW Extension collaborators from the Departments of Biological Systems Engineering, Chemical and Biological Engineering, Soil Science, and Water Resources Management. Funding for the project was provided by Dane County. The team's analysis of the livestock in the Upper Yahara Watershed study area indicates an excess of up to nearly double the manure phosphorus in comparison to crop uptake. The level of excess indicates a need to redistribute the manure outside the study area.
September 16, 2016 – It has been commonly accepted that more cows per pasture would lead to increased nitrogen leaching because of increased nitrogen excretion via urine; but, a new study discovered circumstances where a decline in leaching occurred with increased stocking rate, challenging assumptions about how best to reduce the environmental footprint of grazing systems.
An experiment in New Zealand found that more cows per grazing area led to less nitrogen leached to ground water, challenging assumptions on stocking rate, report investigators in the Journal of Dairy Science.
With population estimates of nine billion people worldwide by 2050, the intensification of agriculture practices in recent decades has been necessary. Significant environmental concerns exist with the intensification of agriculture, however. In dairy farming, particularly on pasture-based dairies, leaching of nitrate-N (NO3-N) to groundwater is a primary concern, leading to certain countries placing limits on herd size on a fixed land area (i.e., stocking rate) to avoid loss of nutrients to groundwater. It has been commonly accepted that more cows per pasture would lead to increased leaching because of increased nitrogen excretion via urine; but, a new study discovered circumstances where a decline in leaching occurred with increased stocking rate, challenging assumptions about how best to reduce the environmental footprint of grazing systems.
The experiment was conducted in New Zealand over two years, with cows divided over 10 farmlets with increasing stocking rates per hectare. The herds were spring-calving, nitrogen fertilizer use was constant across the farmlets, and less than five percent of feed was imported onto the farms. To measure nitrogen leaching, 180 porous ceramic cups were installed in each farmlet at a depth of one meter, and samples were collected every two weeks.
Over the course of the study, total nitrogen consumed and total nitrogen output in milk and meat from the farm increased for every one cow per hectare increase in stocking rate. Fecal and urinary nitrogen excreted per hectare also increased. But, nitrogen intake and milk, fecal, and urine nitrogen output per cow declined with increasing stocking rate. This is particularly important during the autumn months, where urinary N has been implicated in N leaching. Furthermore, the measured amount of NO3-N leached per hectare declined with each one tonne of pasture harvested. Leaching also declined with increasing stocking rate, coinciding with a decline in the concentration of NO3-N in leachate.
The negative association between stocking rate and leaching was possibly due to a reduction in nitrogen intake per cow leading to less urine nitrogen output per cow, a greater spread of urinary nitrogen across the pasture with larger stocking rates, or an increase in pasture nitrogen harvest and an associated increase in milk and meat nitrogen exported and, as a result, less nitrogen available for leaching.
“Globally, dairy systems are being scrutinized for their environmental impact and many are calling for a reduction in cow numbers,” said Journal of Dairy Science editor-in-chief Matt Lucy. “What this new research shows is that grazing more cows per acre of pasture and the associated management strategies that go with this actually reduces any negative impact of grass-based dairies on water quality, provided no additional feed is imported. The result is contrary to the commonly held perception that fewer cows per acre is friendlier to the environment and, instead places the focus on the importation of feed in a pasture system. The study underscores the need for research when developing recommendations for environmentally friendly dairy production.”
This conclusion – that a seasonal, spring-calving, pasture-based dairy production system importing less than five percent of feed with no change in N fertilizer use, had a decline in NO3-N leached per hectare with increasing stocking rate – is a novel one. The authors could not support the idea that lowering stocking rate alone could reduce NO3-N leaching but encourage careful consideration of any changes in stocking rate as a means of changing leaching per hectare. Likewise, future studies should consider a full farm system-level analysis of changes to stocking rate to determine its effect on productivity and environmental outcomes.
September 14, 2016, Saskatoon, Sask – Research conducted by VIDO-InterVac shows the use of heat has the potential to dramatically improve the cleaning and disinfection of swine transport vehicles.
In partnership with Swine Innovation Porc scientists with the University of Saskatchewan, the Prairie Agricultural Machinery Institute, VIDO-InterVac and the Prairie Swine Centre are in the process of developing an automated system for washing and disinfecting of swine transport vehicles to reduce the transmission of infections.
VIDO-InterVac's role is to determine at what temperatures the most common swine pathogens will be inactivated and how long it will take.
Dr. Volker Gerdts, the associate director of research with VIDO-InterVac, says researchers are focusing on the 12 most important pathogens of concern to the industry.
“The first thing we're doing right now in the lab is to essentially just determine after how many minutes, at what temperature these pathogens are inactivated,” he says. “For each of these pathogens we're running a matrix which has various time points, like from one minute to two hours and then the various degrees and we're showing at what temperature each of these pathogens is being inactivated in the lab.”
“Heat in general is very effective in inactivating pathogens.”
“I think what our research is then informing our team members is what temperatures we would have to reach and for how long.”
“That's really then the challenge for the engineers involved in this project, to develop the engineering part, the mechanical part,” says Dr. Gerdts. “Is it possible to heat up a truck or parts of a truck to a certain temperature or what methods can be used to reach that temperature under practical conditions.”
Dr. Gerdts says phase two will be to test these pathogens in the lab in an environment like you would see on a trailer and the third phase will be to repeat the tests in the environment.
He hopes to have the lab work completed by the end of the year.
August 15, 2016, Brookings, SD – Flies are a problem for cattle, but the answer to controlling them could lie with another insect.
Ammonia gas packs a smelly punch. In small doses, it’s what makes smelling salts so effective. But high levels of ammonia can be a health hazard and a pollutant.
Dairy farms are one of the major sources of ammonia emissions. The U.S. Environmental Protection Agency estimated that dairy farms contributed more than 20 percent of the ammonia emitted from animal husbandry operations in 2015.
Now, a recent study has compiled and analyzed data from 25 previous studies. Researchers honed in on factors that influence how much ammonia dairy barns emit.
The goal was to figure out which factors influence ammonia emissions in dairy barns and to, ultimately, lower the amount of ammonia being released from dairy facilities, says Adeline Bougouin, lead author of the study. That’s important because ammonia poses several dangers.
In the confined spaces of many farm buildings, high levels of ammonia can be a threat to animals. Ammonia is also linked to the respiratory problems in humans. In the environment, ammonia can damage terrestrial and aquatic ecosystems.
“Our work is important because it provides key information to farmers and farm advisers about potential ways to lower ammonia emissions,” says Bougouin, a researcher at Wageningen University in The Netherlands who is now working at the French National Institute for Agricultural Research.
But reducing the amount of ammonia being emitted from dairy farms is a complex endeavor. Farms, after all, are economic enterprises. A solution needs to fit with the bottom line.
“Farmers need concrete strategies that reduce the environmental impact of their farms but not their economic output,” says Bougouin.
So, Bougouin and her colleagues looked at existing research.
These studies had cataloged several factors that influence how much ammonia dairy barns release. They looked at both environmental factors, such as seasons and temperature, as well as the diet and nutrition of the dairy cattle.
“We confirmed that both environmental factors and nutritional aspects significantly influence ammonia emissions from dairy barns,” says Bougouin.
Some of the factors influencing ammonia emission – such as seasons – are beyond a farmer’s control. Others are not. Take, for instance, the amount of crude protein in the animals’ diet.
“Crude protein is a measurement of the total amount of nitrogen in feed,” says Bougouin.
Nitrogen in the diet is not broken down efficiently by cattle. It is excreted as urea, mostly through urine. When urine and feces mix, the urea is converted into ammonia and released to the atmosphere.
Bougouin found that reducing the amount of crude protein in a dairy cow’s diet reduced the amount of nitrogen in manure and urea in urine. And it did not affect milk yield. Reducing excess nitrogen in the diet could be an effective strategy to reduce ammonia emissions without affecting a farm’s bottom line.
Other factors that influence the amount of ammonia being released include the type of flooring system used in it, the amount of dry matter in dairy cattle feed, and milk yield per cow.
The findings come with some caveats.
“The emission rates we describe in the study may not represent whole-farm ammonia losses,” says Bougouin.
Emissions can also occur during manure storage or during composting and field application.
Bougouin’s research was published in the Journal of Environmental Quality.
July 4, 2016, McComb, OH — Just off a township road, Duane Stateler’s home, in the distance across a wheat field, is a front line in the debate about what the agricultural industry must do to save Lake Erie.
The Stateler family grows corn, soybeans, and wheat on 600 acres. They also have a pair of finishing barns and a nursery barn, and send 16,000 pigs to market each year. Those hogs produce about 2.3 million gallons of manure annually, which the Statelers spread across their and area farmers’ fields. READ MORE
May 20, 2016, Washington, DC – Emissions from farms outweigh all other human sources of fine-particulate air pollution in much of the United States, Europe, Russia and China, according to new research.
The culprit: fumes from nitrogen-rich fertilizers and animal waste combine in the air with combustion emissions to form solid particles, which constitute a major source of disease and death, according to the new study.
The good news is if combustion emissions decline in coming decades, as most projections say, fine-particle pollution will go down even if fertilizer use doubles as expected, according to the new study published in Geophysical Research Letters, a journal of the American Geophysical Union.
Agricultural air pollution comes mainly in the form of ammonia, which enters the air as a gas from heavily fertilized fields and livestock waste. It then combines with pollutants from combustion – mainly nitrogen oxides and sulfates from vehicles, power plants and industrial processes – to create tiny solid particles, or aerosols, no more than 2.5 micrometers across, about 1/30 the width of a human hair.
Aerosols can penetrate deep into lungs, causing heart or pulmonary disease. A 2015 study in the journal Nature estimates they cause at least 3.3 million deaths each year globally, and a recent study in Geophysical Research Letters found they cause over 500,000 annual deaths in India alone.
Many regional studies, especially in the United States, have shown agricultural pollution to be a prime source of fine-particulate precursors, but the new study is one of the first to look at the phenomenon worldwide and to project future trends. The study's results show more than half the aerosols in much of the eastern and central United States come from farming.
"This is not against fertilizer – there are many places, including Africa, that need more of it," said Susanne Bauer, an atmospheric scientist at Columbia University's Center for Climate Systems Research and NASA's Goddard Institute for Space Studies in New York and lead author of the study. "We expect population to go up, and to produce more food, we will need more fertilizer."
The fact that agricultural emissions must combine with other pollutants to make aerosols is good news, according to Bauer. Most projections say tighter regulations, cleaner sources of electricity and higher-mileage vehicles will cut industrial emissions enough by the end of this century that farm emissions will be starved of the other ingredients necessary to create aerosols, she said.
"You might expect air quality would decline if ammonia emissions go up, but this shows it won't happen, provided the emissions from combustion go down," said Fabien Paulot, an atmospheric chemist with Princeton University and the National Oceanic and Atmospheric Administration, who was not involved in the study.
That means pollutants other than ammonia should probably be targeted for abatement, he said.
Johannes Lelieveld, lead author of the 2015 Nature study, disagreed.
"One should be cautious about suggesting that food production could be increased" without increasing pollution, because that "critically depends" on the assumption that societies will successfully curb industrial emissions, he said. Lelieveld pointed out that even with recent reductions in industrial pollution, most nations, including the United States, still have large areas that exceed the World Meteorological Organization's recommended maximum of particulate matter.
If future industrial emissions do go down, much farm-produced ammonia will end up in Earth's troposphere, roughly two to 10 kilometers (one to six miles) above the surface, Bauer said. There, lightning and other natural processes may also help create fine particulates, but most of these particles would be trapped by raindrops and harmlessly removed from the atmosphere, she said.
OH hog barn equipped with new way to manage manureMay 11, 2017, Madison County, OH – A new hog…
Ranging further afield with fracsCustom manure applicators often describe their work in colorful ways,…
New life for manure digesterMay 19, 2017, Waunakee, WI - Once infamous for spills,…
'Watch-hog' group puts province on noticeMay 19, 2017, Manitoba - An agricultural watchdog group says…
Iowa Manure Calibration & Distribution Field DayFri Jun 02, 2017 @ 1:00PM - 05:00PM
World Pork Expo 2017Wed Jun 07, 2017 @ 8:00AM - 05:00PM
Manure Storage & Handling Safety WorkshopMon Jun 12, 2017 @ 6:00PM - 09:00PM
Anaerobic Digester Operator Training CourseTue Jun 13, 2017 @ 8:00AM - 05:00PM
AgSource Laboratories Ice Cream SocialWed Jun 14, 2017 @ 2:00PM - 04:00PM
Iowa Manure Calibration & Distribution Field DayFri Jun 23, 2017 @ 1:00PM - 05:00PM