Chapter 4.31

4.31 - Covering manure from rain during storage

Huda Nadeem, University of Guelph, Canada

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Suggested citation for this chapter.

Nadeem,H. (2022) Covering manure from rain during storage. In Farmpedia, The Encyclopedia for Small Scale Farmers. Editor, M.N. Raizada, University of Guelph, Canada. http://www.farmpedia.org

Introduction to Manure Management

A huge part of smaller scale farmers is manure management; manure can be one of the most valuable resources they have to enrich their soil with essential nutrients. Manure is made from livestock; it contains nutrients such as nitrogen (N) and phosphorus (P). These are beneficial to soil; however, if exposed to the environment, these precious nutrients can be lost during rainfall (Cheng et al., 2015) by as much as 73%; however the manure can be covered, such as with tarpauline, to help prevent these losses (Cheng et al., 2015). Smallholder farmers in Kenya, Malawi, and Zimbabwe are actively trying to enhance crop production through such manure management practices (Chikowo et al., 2014). By implementing manure management strategies such as covering manure piles during rainfall, farmers can successfully reduce their environmental footprint while enhancing soil nutrients and increasing production efficiency (Chadwick, 2005).

Steps for Manure Management

Agricultural waste materials such as manure from cows, swine or other animals can be used to fertilize fields (Cheng et al., 2015). To utilize this valuable resource to its maximum capacity, farmers can store this manure and protect it from rainfall/uncharacteristic weather patterns. The improper storage of manure can lead to risks associated with water security and environmental pollution.

The management of manure covering is quite accessible and relatively simple. This technique can be adapted by smallholder farmers from local resources. Step one in the process is collecting materials including the manure, and then chopping rice straw around 5 cm in length (Cheng et al., 2015). This rice straw can be from the farmers' local fields. Step 2 is to intertwine these materials prior to piling them into little, strategically placed piles close to the field where the bio-waste starts or the manure can be utilized (Cheng et al., 2015). Step 3 is structuring the blend into little piles, normally flatly shaped into roughly 1 meter in height, length, and width (Cheng et al., 2015). Then to limit the supplement filtering into the rainfall, step 4 is to cover the piles that have been created with material such as film with pores, rice straw or soil at 5 cm in width. This helps to reduce the leachate by speeding up the process of preserving the nutrients and restricting the water within the soil due to rainfall (Cheng et al., 2015). In step 5, the piles need to be turned at intervals of 30 days, three times during the fertilization process; this extensive labor will help to guarantee air circulation and improve the potency of the manure compost (Cheng et al., 2015).

The Benefits of Covering Manure for Farmers

Manure is a valuable resource to not only farmers but also the economy, which is why managing manure more efficiently is extremely important for reducing nutrient loss and has been shown to result in almost twice as much profit (Mazurkiewicz, 2023). Farmers have been shown to benefit from manure management by preserving valuable nutrients and creating richer soil (Mazurkiewicz, 2023). When manure is stored properly, it can contribute to higher nitrogen levels in the soil, accumulating twice as much ammonium nitrogen compared to covered manure alone (Steinberg et al., 2015). A higher nitrogen level in manure can lead to a higher economic gain for farmers. Storing manure can also significantly decrease greenhouse gas emissions (Mazurkiewicz, 2023). Compressing it can also build on the benefits; the quality of methane fermentation in biogas plants can contribute to an alternative form of renewable energy and income for farmers (Mazurkiewicz, 2023).

Properly managing manure can significantly help smallholder farmers, due to its low maintenance costs, but it requires more manual labor and constant monitoring. While this process can be extensive, it can be worth adopting based on the benefits provided.

Critical analysis

There have been advanced technologies created to counteract the loss of nutrients from manure, but these do not align with smallholders. A high-cost solution may not be feasible for smallholder farmers, which is why they may be restricted to using tarpaulin instead of more impactful technologies (Bollwahn, 2021). Though tarpaulin is a cheaper alternative, its maintenance is much more extensive, leading to increased manual labor and a frequent need to monitor in poor weather conditions (Admin, 2021).

Covering manure from unpredictable weather can improve crop production and effectively reduce the need for commercial fertilizers (Chikowo et al., 2014). Crop productivity directly correlates to food security and how smallholder farming can be impacted by this practice (Chikowo et al., 2014). Uncovered manure is susceptible to losing nutrients from rainfall, leading to ecological contamination due to nutrients leaching into the ground (Chikowo et al., 2014). Covering manure can impact the environment in many ways such as reduction in emissions, increased soil fertility and reduced food/water security. A variety of emissions are impacted including ammonia, nitrous oxide, and methane (Chadwick, 2005). For example, compacting and covering beef cattle manure were shown to decrease ammonia (NH3) losses by over 90% during the peak season (Chadwick, 2005).

Similarly, nitrous oxide (N2O) emissions were shown to be reduced by 30% during the starting time frame (Chadwick, 2005). Decreasing nitrous oxide emissions is an important part of ecological management and creates a more sustainable environment. Methane (CH4) was not impacted in the starting time block like nitrous oxide (N2O); however, it showed signs of reduction in the second time-frame roughly, 30 days later (Chadwick, 2005). Nitrous oxide (N2O) and methane (CH4) are harmful substances that negatively impact the environment; reducing these emissions benefits both the farmer and the environment. These results show how covering manure can change how smallholder farmers utilize their resources to make the most profit while also creating a more eco-friendlier environment.

Conclusion

In conclusion, smallholder farmers can benefit in many different ways from proper manure management. It is a practical step they can add to their crop production to enrich their soil with nutrients. There are greater amounts of manual labor associated with having to consistently monitor manure. However, this low cost approach can greater benefits to farmers in the long term (Bollwahn, 2021). Turning and rotating the manure can seem extensive but looking at the carbon emission reduction, farmers can massively benefit from these changes white benefitting the environment and local community.

Practical Links & Resources to get Started

● http://www.sakbooks.com/uploads/8/1/5/7/81574912/5.9e.s.a.pdf Picture versions of manure covering using chopped straws

● http://www.sakbooks.com/uploads/8/1/5/7/81574912/4.3ae.s.a.pdf Picture versions of rainfall destroying nutrients

● https://www.accessagriculture.org/slm12-conservation-agriculture A video on how to reduce costs and improve profitability in soil health, manure management is demonstrated at [4:04] minutes on how to preserve nutrients.

● https://youtu.be/6or-aSA2ruA?si=8xh2L3tc8A5T9jxp A short and simple “how to” clip on manure management

● https://www.fao.org/fileadmin/user_upload/agp/icm12.pdf A detailed volume on how to rotate crops on small farms to understand the procedure with pictures and charts

References

1.Admin, L. (2021, March 5). Storing manure on small farms. Livestock and Poultry Environmental Learning Community. https://lpelc.org/storing-manure-on-small-farms/

2.Bollwahn, S. (2021, July 29). Storing manure on small farms – deciding on a storage option. MSU Extension. https://www.canr.msu.edu/news/storing_manure_on_small_farms_deciding_on_a_storage_option

3.Chadwick, D. R. (2005). Emissions of ammonia, nitrous oxide and methane from cattle manure heaps: effect of compaction and covering. Atmospheric Environment, 39(4), 787–799. https://www-sciencedirect-com.subzero.lib.uoguelph.ca/science/article/pii/S135223100400994X

4.Cheng, J., Qiao, J., Chen, Y., & Yang , Z. (2015). Nutrient loads of small-scale swine manure composting to groundwater and its prevention by covering: a case study. Environmental Science and Pollution Research 22, 15646-15655 (2015). https://doi-org.subzero.lib.uoguelph.ca/10.1007/s11356-015-4705-2

5.Chikowo, R., Zingore, S., Snapp, S., & Johnston, A. (2014). Farm typologies, soil fertility variability and nutrient management in smallholder farming in Sub-Saharan Africa. Nutrient Cycling in Agroecosystems 100, 1–18 (2014). https://doi-org.subzero.lib.uoguelph.ca/10.1007/s10705-014-9632-y

6.Mazurkiewicz, J. (2023). The impact of manure use for energy purposes on the economic balance of a dairy farm. Energies, 16(18), 60-627 (2023). https://mdpi.com/1996-1073/16/18/6735

7.Steinberg, S., Gooch, C., & Czymmek, K. (2015, January). Covered manure storage systems: Tangible and non-tangible benefits. Dairy Business. https://ecommons.cornell.edu/server/api/core/bitstreams/e839e56f-c431-4681-be27-77faa46d1f83/content