Manure and the Environment

Growth in the livestock sector has a lot of potential to benefit Nebraska economically, however it can also have negative impacts on our natural resources. To address some of these environmental impacts, the sector has been working hard to improve livestock water productivity. Recently, scientists at the Daugherty Water for Food Global Institute and the Department of Animal Science of the University of Nebraska, together with colleagues from the University of Twente, and the National University of Singapore worked together to estimate the changes in water productivity of animal products from 1960 to 2016.

Livestock production plays an important role in rural and urban economies worldwide and is a significant source of protein in humans’ diet. However, the growth of the livestock sector can have negative impacts on our natural resources; fresh water consumption, water quality deterioration due to manure nutrient losses to surface water, greenhouse gas emissions, and competition for human-edible grains are all possible consequences of food animal production. To address some of these environmental impacts of livestock production, the sector has been working hard to improve livestock productivity, feed-use efficiency of animals, crop productivity and efficiency of resource utilization in the field, and expanding the sourcing of feeds.

Calling all crop producers who are considering using poultry manure…and rural citizens who want to learn more about poultry manure management!

Algal blooms may occur in bodies of water with excess amounts of nitrogen and phosphorus. These algal blooms are detrimental to fish populations, other animal populations, and possibly human health.

Manure storage and its application on crop land may contribute a form of environmental contamination: antimicrobial resistant bacteria. These bacteria in manure are perceived to cause diseases in humans through environmental contamination. However, a recent study in University of Nebraska-Lincoln feedlots near Mead, Nebraska concluded that long-term manure storage as static stockpiles has the advantage of inactivating antimicrobial resistant bacteria, and it has potential to reduce antimicrobial resistance genes.

Animal agriculture often endures criticism from neighbors and consumers relative to sustainability. But when it comes to management of carbon and nutrients, animal agriculture has a positive story to share. Many environmental and sustainability organizations promote the importance of a “circular economy” for increasing sustainability. Those engaged with Nebraska agriculture should help our neighbors and consumers recognize agriculture’s long term practice of implementing this circular economy. This article will help introduce agriculture’s circular economy for nitrogen (N), phosphorus (P), carbon (C), and other nutrients and messages you might share with neighbors and consumers about the Nebraska Advantage for sustainability.

Agriculture in the United States provides a contribution to greenhouse gases, accounting for 9% of total emissions (US EPA). Animal agriculture is a large contributor. In beef production, both cow-calf operations and feedlots produce these gases. By implementing simple changes in cattle’s diet, though, there are several ways to reduce the number of these greenhouse gas emissions.

It is important that farmers and agriculturalists to implement practices to reduce the runoff of antibiotics. This article helps recognize existing conservation practices one has already implemented that are limiting these risks and additional options that may be considered.

On a brisk April day, I was traveling with a group of adventurers through the wilds of the Minnesota country side. We came upon a steep embankment and climbed it so that we might see what lay beyond. When I reached the top, and the crowd around me had parted, I thought for a moment I might suddenly have traded places with Samwise Gamgee, hobbit, because I was gazing out onto a field of what reminded me very much of the steaming slag pits of Mordor.  However, rather than an apocalyptic hell-scape I was instead looking at a premier example of sustainable agriculture.

An undesirable combination of precipitation events and freeze/thaw cycles has contributed to some very muddy feedlot surfaces in the winter and spring of 2019 in Nebraska. Preventative design and management options exist for minimizing the occurrence and extent of muddy open feedlot conditions, but very few ‘fixes’ exist for addressing muddy conditions once they are in place. Additional information on your options follows...

Growth in Nebraska’s livestock and poultry industries is greatly influenced by county zoning and local decision-making. Variation in policies among counties and in decisions made by county officials creates significant challenges for current and prospective livestock operations and for rural communities looking to remain vibrant and create new revenue to support local resources. The Nebraska Livestock Siting Assessment Matrix is approved for use and recently updated for continued dissemination by the Nebraska Department of Agriculture.

Iowa State University researchers concluded from a long-term field study that poultry manure, when applied at a rate to meet the crop nitrogen (N) requirements, can reduce nitrate loss and achieve equal or better yields in corn soybean production systems. While this research focused on nitrate (NO­3-N) loss by field-tile drains (typically placed 3 to 6 feet deep), similar trends would be anticipated in Nebraska for nitrate leaching below the crop root zone and the eventual impacts on surface and ground water quality.

Abandoned manure storages present a risk to the environment by accidental overflow or leakage due to lack of management. It is in the best interest of the environment and the property owner, who is liable for any environmental damage resulting from any discharge, whether leakage or overflow, to properly close any unused manure storage structure.

Management is the key to keeping dust under control. By using some basic dust control techniques, open feedlots can prevent or minimize the problem.

Because of a growing concern about manure irrigation, the University of Wisconsin Extension assembled a workgroup to research the concerns. The workgroup included scientists, public health specialists, state agency experts, farmers, conservationists and others. Over the course of two years, the group gathered and studied the science of manure irrigation, which culminated in a report that contains findings, responses and recommendations. This article will review a few of their findings related to bacterial transport as well as highlight some of the reasons why a farmer might opt to apply manure via irrigation rather than other ways.

When designed properly, runoff holding ponds, lagoons, and other earthen manure storage structures are sized to contain manure, process wastewater, and storm water that drain into or fall on them throughout their designed storage period. Excess precipitation, particularly chronic wet weather, can lead to concerns about storages overflowing even when they have been managed correctly.

Manure is often viewed by many as an environmental liability. However, if manure is applied at rates equal to or less than the nitrogen (N) requirement of a crop, can manure produce environmental benefits over commercial fertilizer? This was the focus of an Asian research group which summarized the results of 141 published studies from Asia, Europe, and the U.S. comparing manure substitution for fertilizer. This article summarizes the “Take Home Messages” from this research paper.

Winter cereal rye planted as a cover crop has been shown effective in capturing nitrate before it leaches from the root zone. We conducted on-farm trials in central and southern Minnesota to determine if a rye cover crop would capture significant root-zone nitrate in the fall and spring but release it in time to maintain yield in the subsequent corn crop.

Land application of organic materials for soil management in Nebraska is important. The availability of applied organic N and the fertilizer N substitution values of applied organic materials is not well predicted. The uncertainty of applied organic N availability leads to over-application of fertilizer N resulting in low efficiency of applied N use. Research has been done to validate or adapt canopy sensor guided in-season N application practices for fields with manure or other organic material applied, and to improve the prediction of the fertilizer N substitution values for organic materials.

Soil health management refers to the preservation and improvement in soil physical, chemical, and biological properties to maximize the productive capacity of soil. Cover crops and reduced tillage are promoted for improving soil health; however, soil amendments such as application of livestock manure and municipal biosolids have received less attention as a soil health improvement practice. A literature review, funded by the North Central Region Water Network and the Soil Health Institute, was conducted to summarize and discuss results of studies reporting chemical, physical, and biological soil properties from application of livestock manure, animal by-products (i.e. compost), and municipal biosolids and to identify further research needs.