Organic Farming: Assessing Nitrogen Accessibility from Manure and Compost in Agriculture
Poultry manure is a rich source of nutrients for soil fertility, particularly nitrogen (N), phosphorus (P), and potassium (K). However, the nitrogen in poultry manure is primarily in organic forms, with only a small fraction immediately available for plant uptake [1][3].
Properly composted poultry manure offers elevated levels of nutrients compared to general compost and cow manure, making it a valuable resource for organic farming. Laboratory analysis is recommended to determine the actual nitrogen content of the source material [1]. The uniformity of the material is important, especially in straw pack manure [1].
The number of spreader loads per field can be calculated based on the determined capacity. Calibration of spreaders improves the accuracy of application rates [1]. The amount and type of bedding added to manure affects its nitrogen content and availability [1]. As manure and compost are stored over time, nitrogen losses may occur due to exposure to the atmosphere [1]. A factor of 25 percent loss is typically used to account for losses of nitrogen over time and during handling [1].
Not all the nitrogen applied as manure or compost is immediately available to the crop, with first year available organic nitrogen estimated at 33% [1]. Compost is a more stable material and will have less volatilization losses compared to manures [1]. The type of additives used to create compost influences its nitrogen content [1].
Organic producers need to have an understanding of plant available nitrogen derived from compost or manure sources for cereal grain crops like corn, wheat, oats, and spelt [1]. Delaying incorporation for even one day under warm and dry soil conditions could result in additional 50% loss of ammonium nitrogen [1]. Immediate incorporation or injection of manure or compost minimizes losses of ammonium nitrogen to the atmosphere [1].
The amount of liquid contained in the manure or compost affects the concentration of nitrogen per ton applied [1]. The uniformity of the material is important, especially in straw pack manure [1]. Components such as leaves, corn stalks, straw, wood chips, or other organic materials vary greatly in their nitrogen content [1].
In contrast, phosphorus and potassium in poultry litter tend to be 90-100% available during the growing season [3]. This slow nitrogen release requires organic producers to carefully manage poultry manure applications, often basing rates on the crop’s phosphorus needs to prevent phosphorus buildup in soil, which can result from applying manure based on nitrogen requirements [3].
Compared to synthetic fertilizers, poultry manure enriches soil organically without the environmental impacts linked to energy-intensive synthetic fertilizer production, but it can cause ammonia emissions during decomposition [2]. For organic producers, managing poultry manure involves composting to reduce pathogens, considering nitrogen availability over time, and aligning application rates with crop nutrient requirements to optimize nutrient use efficiency and reduce environmental risks [1][3].
In summary, the higher nutrient content but slower nitrogen availability of poultry manure compared to other manures and composts influences organic nutrient management plans by necessitating composting to enhance safety and nutrient stability, applying manure rates based on phosphorus rather than nitrogen to avoid nutrient imbalances, recognizing the gradual nitrogen release, timing applications to match crop demand, and integrating poultry manure into crop rotations and soil testing regimes for sustainable nutrient inputs [1][3].
- Poultry manure is a valuable resource for organic farming due to its rich nutrients, including nitrogen, phosphorus, and potassium.
- The nitrogen in poultry manure is primarily in organic forms, with only a small fraction immediately available for plant uptake.
- Properly composted poultry manure offers elevated levels of nutrients compared to general compost and cow manure.
- Laboratory analysis is recommended to determine the actual nitrogen content of the source material.
- The uniformity of the material is important, especially in straw pack manure.
- The number of spreader loads per field can be calculated based on the determined capacity.
- Calibration of spreaders improves the accuracy of application rates.
- The amount and type of bedding added to manure affects its nitrogen content and availability.
- As manure and compost are stored over time, nitrogen losses may occur due to exposure to the atmosphere.
- A factor of 25 percent loss is typically used to account for losses of nitrogen over time and during handling.
- Not all the nitrogen applied as manure or compost is immediately available to the crop.
- Compost is a more stable material and will have less volatilization losses compared to manures.
- The type of additives used to create compost influences its nitrogen content.
- Organic producers need to have an understanding of plant available nitrogen derived from compost or manure sources for cereal grain crops.
- Delaying incorporation for even one day under warm and dry soil conditions could result in additional 50% loss of ammonium nitrogen.
- Immediate incorporation or injection of manure or compost minimizes losses of ammonium nitrogen to the atmosphere.
- The amount of liquid contained in the manure or compost affects the concentration of nitrogen per ton applied.
- Components such as leaves, corn stalks, straw, wood chips, or other organic materials vary greatly in their nitrogen content.
- In contrast, phosphorus and potassium in poultry litter tend to be 90-100% available during the growing season.
- This slow nitrogen release requires organic producers to carefully manage poultry manure applications.
- Organic producers should base rates on the crop’s phosphorus needs to prevent phosphorus buildup in soil.
- Poultry manure enriches soil organically without the environmental impacts linked to energy-intensive synthetic fertilizer production.
- For organic producers, managing poultry manure involves composting to reduce pathogens.
- It is important to align application rates with crop nutrient requirements to optimize nutrient use efficiency.
- Sustainable nutrient management plans should consider the gradual nitrogen release.
- Timing applications to match crop demand is essential for reducing environmental risks.
- Integrating poultry manure into crop rotations and soil testing regimes is necessary for sustainable nutrient inputs.
- The higher nutrient content but slower nitrogen availability of poultry manure influences organic nutrient management plans.
- Proper management of poultry manure involves considering nitrogen availability over time.
- Managing poultry manure is crucial for optimizing nutrient use efficiency and reducing environmental risks.
