Manure and the Environment

Manure contains four primary contaminants that impact water quality: nitrogen, phosphorus, bacteria and other pathogens, and organic matter. Achieving a nutrient balance will reduce potential environmental hazards often associated with animal agriculture. An annual crop nutrient management plan is needed to ensure an adequate supply of nutrients to sustain profitable crop production, and to balance nutrient inputs (including manure) with crop nutrient needs.

Thursday October 12, 2017

Manure Impact on Erosion and Runoff

This article reviews the value that results from changes to soil’s physical characteristics. Charles Wortmann and Dan Walters, faculty with the University of Nebraska-Lincoln monitored soil erosion, runoff, and phosphorus (P) loss from replicated field plots over three cropping seasons immediately after manure application and four subsequent years when no manure was applied. Significant erosion and runoff benefits were observed for sites receiving animal manures.
Thursday September 14, 2017

Manure Impact on Soil Aggregation

Manure increases formation of larger and more stable soil aggregates. Several benefits result for fields fertilized by manure compared to commercial fertilizer including reduced runoff and soil erosion and increased water infiltration leading to greater drought tolerance.
Wednesday August 16, 2017

Siting Animal Facilities to Reduce Neighbor Nuisance

Wind direction and speed affect dust and odor risk. A first step in assessing and minimizing potential dust and odor nuisance risk of a livestock operation is identifying the most likely downwind directions. This article will share wind frequency data for 44 Nebraska locations to consider siting options for reducing these nuisances.

Odor Footprint Tool

The Odor Footprint Tool (OFT) estimates the frequency of annoying odor events around an existing or proposed livestock facility and uses this information to determine minimum separation distances that should be maintained around those facilities and to help in siting decisions.

Odor Management

Odor emission is of great concern to the general public. An odor management plan is required in the permit application for livestock operations with more than 1,000 animal units. Producers need to understand odor emission from animal housing, manure storage and handling, and land application and available management options.

Manure Nutrient Losses

Manure nutrients are lost during manure handling, storage, treatment, and application. Manure nitrogen is especially vulnerable to volatilization when ammonium is transformed to ammonia. Losses of phosphorus and potassium are primarily due to runoff and erosion.

Pathogens and Organic Matter

Pathogens, typically microbes (e.g., bacteria, viruses, protozoa, fungi) or parasitic worms, are organisms capable of causing infection or disease in other organisms, including humans, wild and domestic animals, and plants. Several pathogens naturally occur in livestock and poultry manure and under certain circumstances may pose a risk to human health.

EPCRA Emissions Rule for Livestock and Poultry

On December 18, 2008, the US EPA published a final rule that clarified which livestock facilities must report air emissions from their facilities. Animal agriculture was granted an administrative exemption from reporting air emissions that normally occur from raising farm animals under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA).

OFT Worksheet Version

Step-by-step instructions for using the worksheet version of the Odor Footprint Tool and an example completed worksheet are provided in the following documents.

Air Quality Issues

The federal Clean Air Act Amendment of 1990 (CAAA) has provisions of importance to producers of agricultural products. Although protecting air quality has inherent implications for livestock and poultry health as well as profitability, the language of air quality is derived principally from environmental regulations designed to protect public health and the use and enjoyment of private property.

Phosphorus Loss

Land application of manure can be beneficial to crop production but can result in increased risk of P loss to surface waters. When manure is applied to meet crop nitrogen needs, the amount of P applied is typically much more than the P removed in the harvest of one crop. Effective January 1, 2007, operators of large CAFOs in Nebraska need to assess the risk of P delivery to surface waters from each of their designated fields by using a P index before manure can be applied.

Contaminant Pathways

Water quality can be degraded by contaminants contained in manure, from water used at milking centers, from silage leachate, and from open lot runoff. These potential pollutants typically follow one or more possible pathways to water.

Pig Production Environmental Sustainability Footprints

A Nebraska Extension pilot project is assisting pork producers in calculating their swine farm environmental sustainability footprints in a joint effort with the University of Minnesota Extension.

Environmental Planning

Large animal feeding operations (AFO's) must follow regulations to protect water quality and preserve the environment. Smaller operations can help the environment as well. Livestock Producer Environmental Assistance Project (LPEAP) works with small farms to implement appropriate technologies and best management practices designed to protect water resources and our environment.

Air Quality

The University of Nebraska is addressing air quality issues associated with animal agriculture in several ways because good air quality is very important to Nebraskans.

Controlling Emissions

Good stewardship calls upon livestock and poultry producers to limit emissions of air pollutants where feasible. Odor control practices and technologies may take several forms. Information on control strategies may focus upon the type of emissions controlled or the source of air emissions.

Phosphorous Dynamics

Animal manures contain both organic and inorganic forms of phosphorus. When manure mineralizes, organic phosphorus becomes inorganic phosphorus in solution and is available to plants. Some organic phosphorus is transformed to inorganic form shortly after application but other phosphorus will remain in organic form

Nitrogen Dynamics

Nutrients in manure are potentially valuable resources for the management of soil fertility, but these nutrients are potential pollutants as well. Only 10 to 40 percent of the nutrients consumed by animals may end up in the marketed product; the rest is excreted in feces and urine. Manure contains all nutrients needed by plants, but nitrogen and phosphate generally have the most agronomic significance in Nebraska.

Understanding Water Quality Issues

Manure contains four primary contaminants that impact water quality: nitrogen, phosphorus, bacteria and other pathogens, and organic matter.

Small Farm Issues

Many of the manure management and environmental resources and publications are written for large livestock operations. Yet, most of the farming operations in the US are small. In Nebraska, for example, nearly 70% of all beef operations are less than 300 head and 90% are less than 1,000 head.