EFFECT OF SOLID CATTLE MANURE AND LIQUID HOG MANURE APPLICATION ON PHOSPHORUS AND NITROGEN IN SOIL, RUN-OFF AND LEACHATE IN SASKATCHEWAN SOIL

Abstract

Traditional application methods in which manure is simply broadcast on the soil surface are being replaced by innovative methods that place the manure in the soil in bands, potentially increasing efficiency of manure nutrient utilization by crops and reducing losses to the environment. Limited information exists on the pools and mobility of phosphorus (P) and nitrogen (N) in soils receiving repeated applications of animal manure using different application methods. The overall objective of the thesis research is to determine the fate of manure nutrients applied using new subsurface banding technology, as it affects crop response and uptake, residual nutrients in the soil, and transport (lateral and vertical) by water off-site. Specific objectives were: 1) to determine yield response to solid cattle manure (SCM) and the recovery of SCM and liquid hog manure (LHM) P and N using broadcast manure placement and new subsurface banding technology, 2) to determine the amount of soluble reactive phosphorus (SRP) and N that is transported in snowmelt water moving across soils receiving different rates and methods of application of manure, and 3) to determine the amount and proportion of SRP and N that are transported downward in a SCM amended soil profile with leaching water as influenced by manure rate and placement. In-soil placement of SCM in bands had a small impact on improving crop yield and nutrient uptake in a 3 year crop rotation in east-central Saskatchewan compared to broadcast, and broadcast and incorporate application strategies. In-soil placement of manure was also not effective in reducing P and N export in snowmelt water. Export of P and N downward in leachate water in intact cores was increased by in-soil manure placement, especially when placed in bands. This is attributed to reduced fixation of manure N and P and enhanced solubilization when manure is placed in soil in bands versus a broadcast application. Overall, nutrient export was significantly lower in frozen versus thawing soils, and export of P in soils receiving liquid hog manure was much less than in soils receiving solid cattle manure which is attributed to the higher P content in cattle manure.