Nitrification inhibitor treatment of grazed pasture soils

• US 20060089260A1
• Filed: 08/01/2003
• Published: 04/27/2006
• Est. Priority Date: 08/02/2002
• Status: Abandoned Application

• Current Assignee: Lincoln University, Ravensdown Fertiliser Co-Operative Limited
• Original Assignee: Lincoln University, Ravensdown Fertiliser Co-Operative Limited
• Inventors: Cameron, Keith Craig, Di, Jie Hong
• Application Number:
  US10/522,948
• Publication Number:
  US 20060089260A1
• Time in Patent Office: Days
• US Class Current: 504/116.100
• CPC Class Codes: A01C 21/00 Methods of fertilising , sowing or planting
• CPC Class Codes: C05G 3/90 for affecting the nitrification of ammonium compounds or urea in the soil
• CPC Class Codes: Y02P 60/21 Dinitrogen oxide [N2O], e.g. using aquaponics, hydroponics or efficiency measures

Abstract

A nitrification inhibitor treatment used as a soil mangement tool on grazed pasture soils. The treatment includes the application of nitrification inhibitors in solution form and/or line particle suspension form and/or in crystalline form to treat the whole area of grazed pasture soils to: reduce nitrate leaching; reduce nitrous oxide emissions; reduce postassium, calcium and magnesium leaching; and increase pasture production in both the animal urine patch areas and non-urine patch areas. The nitrification inhibitors can be applied in conjunction with irrigation water, by a spray vehicle or in a similar way to the application of agricultural chemicals.

Claims

1-35. -35. (canceled)

36. A method for soil management in pasture farming systems, comprising applying a nitrification inhibitor in solution form, fine particle suspension, or crystalline form to treat an entire area of grazed pasture soils, to reduce at least one of (1) NO₃⁻

—

N leaching, (2) nitrous oxide emission; and

(3) potassium, calcium or magnesium leaching, whereby pasture production in both animal urine patch areas and non-urine patch areas is increased.

37. A method according to claim 36, wherein the nitrification inhibitor is applied in conjunction with either irrigation water by a spray vehicle, or by conventional method for application of agricultural chemicals.

38. A method according to claim 36, wherein the nitrification inhibitor is applied in the autumn at a frequency and time that reduces NO₃⁻

—

N leaching by about 76% for urine-N.

39. A method according to claim 36, wherein the nitrification inhibitor is applied in the spring at a frequency and time that reduces NO₃⁻

—

N leaching by about 42% for urine-N.

40. A method according to claim 38, wherein the nitrification inhibitor is further applied in the spring at a frequency and time that reduces NO₃⁻

—

N leaching by about 42% for urine-N, resulting in a annual average reduction of about 59%, which is equivalent to reducing NO₃⁻

—

N leaching loss in a grazed pasture from about 118 to about 48 Kg N ha<sup>−

1</sup> y<sup>−

1</sup>.

41. A method according to claim 36, wherein the nitrification inhibitor is dicyandiamide (DCD), nitropyrin or 3,4-dimethylpyrazole phosphate (DMPP).

42. A method according to claim 36, wherein the nitrification inhibitor is in the form of solution or fine particle suspension, whereby permeation of the inhibitor throughout a soil surface layer is enhanced, increasing the soil volume treated and slowing down the decomposition of the inhibitor.

43. A method according to claim 36, wherein the nitrification inhibitor is applied multiple times to maintain and prolong the inhibition effect in the soil.

44. A method according to claim 36, wherein the nitrification inhibitor is applied in crystalline form, which allows for its dissolution by rain or irrigation water.

45. A method according to claim 36, wherein the NO₃⁻

—

N concentration in a drainage water from the grazed dairy pasture soil is reduced from about 19.7 to about 7.7 mg N L<sup>−

1</sup>.

46. A method according to claim 41, wherein a solution of DCD is applied to the grazed pasture at a frequency and timing to increase pasture production from the whole of grazed pasture by more than 15%.

47. A method according to claim 46, wherein the application of DCD reduces total annual NO₃⁻

—

N loss from about 488 to about 112 kg N ha<sup>−

1</sup> y<sup>−

1</sup>.

48. A method according to claim 41, wherein urea is applied at 200 kg N ha⁻

1 y<sup>−

1</sup> throughout the pasture and the pasture is grazed by 3 cows per ha., wherein DCD is applied to the whole area of the grazed pasture soil, and wherein the average annual NO₃⁻

—

N leaching loss is reduced from about 118 kg N ha<sup>−

1</sup> y<sup>−

1</sup> to about 46 kg N ha<sup>−

1</sup> y<sup>−

1</sup>.

49. A method according to claim 41, wherein pasture N off-take as a result of DCD application is increased by an equivalent of about 23% for autumn urine treatments, and about 9% for spring urine treatment, resulting in an annual average of about 16%.

50. A method according to claim 41, wherein DCD application to the whole area of grazed pasture soil increases pasture yield from about 11.1 t to about 13.0 t ha⁻

1 y<sup>−

1</sup>.

51. A method according to claim 41, wherein DCD is applied five times in a spring urine treatment, or nine times in an autumn urine treatment, or both.

52. A method according to claim 41, wherein DCD is applied in a spring and an autumn application each year.

53. A method according to claim 36, wherein application of the nitrification inhibitor reduces calcium leaching by about 50% (from about 213 to about 107 kg/ha/y), potassium leaching by about 65% (from about 48 to about 17 kg/ha/y), and magnesium leaching by about 52% (from about 17 to about 8 kg/ha/y).

54. A method according to claim 36, wherein application of the nitrification inhibitor reduces nitrous oxide emission following urine application in the autumn from about 26.7 kg N₂O—

N ha<sup>−

1</sup> to about 7.2 kg N₂O—

N ha<sup>−

1</sup>.

55. A method according to claim 36, wherein application of the nitrification inhibitor reduces nitrous oxide emission following urine application in the spring from about 18.0 kg N₂O—

N ha<sup>−

1</sup> to about 4.5 kg N₂O—

N ha<sup>−

1</sup>.

56. A delivery mechanism for applying a nitrification inhibitor, which is in solution, in fine particle suspension, or both, to the whole area of soil in a grazed pasture system, wherein the nitrification inhibitor reduces at least one of (1) NO₃⁻

—

N leaching, (2) nitrous oxide emission;

(3) potassium, calcium or magnesium leaching, whereby pasture production in both animal urine patch areas and non-urine patch areas is increased, wherein the nitrification inhibitor is applied in conjunction with either irrigation water, or applied as conventional agricultural chemicals.

57. A delivery mechanism according to claim 56, wherein the nitrification inhibitor is supplied to an irrigator by a computer controlled system.

58. A delivery mechanism according to claim 56, wherein the nitrification inhibitor is injected from a supply tank into irrigation water using a flow rate controlled pump connected to an irrigation delivery pipe or irrigation hose.