Urine patch size and nitrogen load: effects on nitrogen uptake from the urine patch in plantain and ryegrass/white clover pastures
Field measurements from micro-plots (0.20 - 0.36 m2) of perennial ryegrass/white clover and of pure plantain were used to mimic a urine patch (UP) and to test the effects of UP nitrogen (N) load and size on pasture N offtake. Urine N offtake was greater with plantain than with standard pasture; however, the relative contribution to uptake from the wetted area and surrounding edge was the same for both species. Most (>90%) of the apparent offtake of urine N by plantain and standard pastures was within 20 cm of the edge of the UP. For the two urine patch sizes tested, edge contribution to urine N offtake was on average about 30% of the total from the UP, but was higher for at 600 kg N/ha urine N (45%) than at 300 kg N/ha (18%). Understanding this edge contribution is important for model improvement, and for the development of mitigations to decrease N leaching.
This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.
This work is licensed under a Creative Commons Attribution-Non Commercial-NoDerivatives 4.0 International License. Rights granted to the New Zealand Grassland Association through this agreement are non-exclusive. You are free to publish the work(s) elsewhere and no ownership is assumed by the NZGA when storing or curating an electronic version of the work(s). The author(s) will receive no monetary return from the Association for the use of material contained in the manuscript. If I am one of several co-authors, I hereby confirm that I am authorized by my co-authors to grant this Licence as their agent on their behalf. For the avoidance of doubt, this includes the rights to supply the article in electronic and online forms and systems.