The advantages of biosolids in agriculture are clear. They are naturally abundant in nutrients such as nitrogen and phosphorus that help farmers enrich the soil without the use of chemical fertilizers. Because they contain organic matter, they are less water soluble and the nutrients are less likely to leach into groundwater or be easily washed away through surface run off. The slow-release of key nutrients allows plants to be nourished over a longer period of time. Biosolids also possess micronutrients such as iron and zinc that plants need for healthy development. This results in increased crop production after fertilization with biosolids. Here’s a list of the environmental benefits of biosolids:
Prevents Soil Erosion
Because biosolids contain organic matter, they are useful as major binding agents for aggregate formation and stabilization. They help bind soil together improving texture and reducing soil erosion as well as enhancing water holding capacity. They encourage root growth making vegetation more resistant to droughts. Biosolids can act as soil conditioners resulting in optimum soil structure and improving the physical and chemical properties of soils.
Less Likely to Cause Algae Blooms
Excess nitrogen and phosphorus from agricultural fields can reach bodies of water through surface run-off. One effect of this nutrient pollution is the overgrowth of algae known as algae blooms. The algae blooms produce harmful toxins and create dead zones where very low oxygen levels result in fish kill. All types of crop fertilizer can contribute to this problem. But because biosolids are less water soluble, the possibility of the nutrients getting into the water system is much lower. Since they also improve soil structure, less nutrients leech out of the soil.
Reduces Need for Mining Minerals
The production of chemical fertilizers relies on the mining of phosphorus and potassium minerals in the form of ore deposits available from the earth’s crust. These mining activities can cause negative environmental impacts. These may include disturbing the landscape through removal of topsoil and vegetation, groundwater contamination, excessive use of water resources, and emission of dust or toxic gases. One of the key environmental benefits of biosolids is the upcycling of phosphorus and potassium reduces the need to mine minerals to produce chemical fertilizers.
Stores Carbon and Offsets Greenhouse Gases
Biosolids have the added environmental benefit of fixing carbon away from the atmosphere. According to a study published in Applied Soil Ecology, “the use of biosolids can change agricultural soils from prevalent Carbon-neutral to a Carbon sink which helps offset global CO2 emissions”.
Storing the carbon in the soil is seen as a form of carbon sequestration. This helps lessen the carbon footprint and addresses some challenges associated with climate change.
Furthermore, synthetic fertilizers consume a huge amount of fossil fuels to produce. By reducing the use of synthetic fertilizers, emissions from non-renewable energy sources are also minimized. In fact, certain methods used to treat biosolids actually create energy in the form of biogas. Biogas can be captured during anaerobic digestion and methane utilized to power operations rather than purchasing gas or electricity.
Reclaim Areas Destroyed By Mining
Biosolids can be employed to rehabilitate highly contaminated mining sites, quarries and landfills. They can stabilize and improve the soil fertility of areas destroyed by these activities. Alkaline-stabilized biosolids can also be used as a substitute for intermediate and final landfill cover. The ability of organic matter to provide slow-release nutrients allows revegetation of devastated sites.
If you are a municipality in Ontario and in need of a biosolids management solution, please feel free to contact us at 1 (877) 479-1388.
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