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Cropping Practices to Reduce Nutrient Losses in Runoff

Important Terms

Table 8.2.1 Key Terms and Definitions

Term Definition

Contour Following the lay of the land perpendicular to direction of the slope. Crop Biomass The total plant matter produced by the crop (i.e., straw, roots and seed). Direct Seeding

In this cropping system, no tillage operations are completed prior to the seeding of the crop. Generally, the crop is seeded directly into the stubble of the previous crop. Percolates The movement and filtering of fluids through porous materials (i.e., soil).

Reduced Tillage

In this cropping system, tillage operations are minimized leaving most of the plant residue on the soil surface. The primary tillage operation is seeding. The amount of soil disturbance varies with the equipment used. Reduced tillage systems replace most weed control tillage operations with herbicide applications. Terraces

A leveled section of a hilly cultivated area designed as a method of soil conservation to slow or prevent the rapid runoff of surface water.

Zero Tillage or No-Tillage

This is a conservation cropping system in which the only operation that disturbs the soil is seeding and any simultaneous fertilizer application. While the amount of soil disturbance varies with the equipment used, in most practical situations only 10 to 30 % of the soil is disturbed.

more info

This chapter is meant to provide an overview of the erosion control benefits of selected practices. For more details about these practices consult the suggested references for each topic, contact Alberta’s Ag-Info Centre, or contact a qualified consultant or service provider.

This chapter will focus on management practices that are designed to prevent nutrient losses in runoff, primarily through addressing ground cover and slope. The practices discussed in this chapter generally do not require additional, specialized equipment and are cost-effective in contrast to installing more intensive runoff control measures, which are discussed in Chapter 8.3.

Manure application and no-tillage situations can increase the occurrence of nutrients on or near the soil surface and subsequently increase the amount of potential dissolved nutrients in water. Management practices that take into account the characteristics of runoff can be adopted to minimize the potential nutrient loss due to runoff. Practices that are effective at reducing nutrient losses from a field either reduce the source of nutrients on or close to the soil surface or reduce the flow of runoff.

Practices designed to reduce water erosion and nutrient losses from runoff generally fall into:

Practices that manage the application of manure • Practices that attempt to disrupt the continuity of a • slope Practices that maintain or enhance ground cover • Practices that reduce soil compaction •

Practices that Manage the Application of Manure

Avoid Applying Manure on Snow-covered or Frozen Ground

Manure spread on snow-covered or frozen ground is in direct contact with snowmelt runoff water increasing the risk of nutrient transport. Higher levels of nutrients have been measured in runoff from land where manure was winter-applied as compared to non-manured land. Eliminating or minimizing winter application of manure reduces the chance of nutrient loss during runoff.