Plant nutrients are elements that are essential for plant growth and reproduction that are available in the soil (e.g. nitrogen, phosphorus, and potassium), or from air or water (carbon, hydrogen, oxygen). When existing soil nutrients cannot produce good crop yields, additional nutrients must be added. Nutrients are added to the soil from commercial fertilizers or from organic sources such as manure, compost or biosolids.
Nutrient management involves using crop nutrients as efficiently as possible to improve productivity while protecting the environment. The key principle behind nutrient management is balancing soil nutrient inputs with crop requirements. When applied in proper quantities and at the right times, added nutrients help achieve optimum crop yields; applying too little will limit yield and applying too much does not make economic sense and can harm the environment. Nutrients that are not effectively utilized by crops can potentially leach into groundwater or enter nearby surface waters. Too much nitrogen or phosphorus for example can impair water quality.
A major focus of nutrient management planning is to prevent the over-application of nutrients to protect water quality and minimize impact on the environment while still providing optimum yield for economic benefit. It involves accounting for and recording all the nutrients you have, determining what nutrients you will need, and planning how, how much, when and where to apply them to your crop land. This involves first determining what nutrients are in the soil (soil-testing) and what’s available in a growing or harvested crop, and then determining what has to be added to meet the needs of crops. This plan will lay out how nutrients are managed according to land base characteristics, crops being grown, type of nutrient, proximity to water and application methods. Records of nutrient application rates, methods and timing help with future planning.
Nutrient management planning helps to reduce contamination to waterways by plant nutrients. Without proper management, nutrients can dissolve in soil water and go into surface or ground water through leaching or runoff. This could contaminate surface and groundwater, and on-farm drinking water, community wells and other drinking water sources can be affected. Valuable nutrients could be lost, resulting in reduced crop yields or additional costs for commercial fertilizers.
The management, land application and storage of nutrients that are applied to agricultural land are regulated under the Nutrient Management Act and O. Reg. 267. This includes materials generated on farms such as manure and animal bedding, and materials generated by non-agricultural operations such as sewage biosolids, pulp and paper biosolids and other by-products that benefit crop growth. The regulation sets out specific requirements for planning, storage requirements, and land application standards including maximum application rate and setbacks from wells and surface or ground water.