Impacts of New Phosphorous Regulations on Composting of Animal Manures

The Problem

Concerns are mounting in states that have sensitive waterways about the release of P from manure and compost into ground and surface water. P is the limiting nutrient for many freshwater ecosystems and as such regulate the rate of eutrophication and oxygen depletion. The concerns have led to new regulations that limit the application of manure and in some cases compost products that have high concentrations of P.  

Predicting Manure Nitrogen and Phosphorus Characteristics of Beef Open Lot Systems

This project involves the analysis of a new data set for manure characteristics from open lot beef systems demonstrating both average characteristics and factors contribution to variability in manure characteristics among these systems. Defining the characteristics and quantities of harvested manure and runoff from open earthen lot animal systems is critical to planning storage requirements, land requirements for nutrient utilization, land application rates, and logistical issues, such as equipment and labor requirements.

Comparison of Struvite to Mono-Ammonium-Phosphate as a Phosphorus Source on Commercial Alfalfa Fields

The purpose of this project was to demonstrate a regional nutrient (phosphorus (P)) recycling relationship between the dairy industry and alfalfa forage growers. Dairies often have excess P in manure in relation to the need for crop production on-farm. Easily mineable reserves of phosphorus (P) worldwide are limited, with a majority residing in Morocco (USGS 2013).

Macropore Characterization to Enable the Selection of Practices that Minimize Soluble Phosphorus Loss

Soluble nutrients are believed to be contributing to the recent high-profile impacts in the Great Lakes including excessive cyanobacteria growth (Ohio 2010; Baker et al. 2014).   Retaining nutrients, and especially phosphorus in the Great Lakes region, on crop land is also important to the producer as it is non-renewable, scarce, expensive, exhibits high price variability, and can cause adverse environmental impacts when discharged into fresh water systems.

Phosphorus Release from Sewage Sludge Incinerator Ash in a Corn and Soybean Field Study

In the Twin Cities, sewage sludge is incinerated and in the process 5 MW of power is generated per day.  Incineration produces significant amounts of ash (38 tons/day) which contains nearly 30% total phosphate (P2O5).  Currently, sewage sludge incinerator ash (SSA) is landfilled at a cost to taxpayers, but previous studies have shown that the ash has the potential to be a source of phosphorus (P) for crop production.