1 / 41

P. Schweigert* and R.R. van der Ploeg Institute of Soil Science, University of Hannover,

Monitoring soil mineral nitrogen concentration in Germany: Preliminary results and some methodical challenges. P. Schweigert* and R.R. van der Ploeg Institute of Soil Science, University of Hannover, Hannover, Germany. N surplus of agricultural land in Germany. Consequences of N surplus.

marybutler
Download Presentation

P. Schweigert* and R.R. van der Ploeg Institute of Soil Science, University of Hannover,

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Monitoringsoil mineral nitrogen concentration in Germany: Preliminary resultsand some methodical challenges P. Schweigert* and R.R. van der Ploeg Institute of Soil Science, University of Hannover, Hannover, Germany

  2. N surplus of agricultural landin Germany

  3. Consequences of N surplus • Soil mineral nitrogen increased

  4. Consequences of N surplus • Soil mineral nitrogen increased • Nitrate leaching increased

  5. Consequences of N surplus • Soil mineral nitrogen increased • Nitrate leaching increased • Nitrate concentration in groundwater often increased over 50 mg l-1 • Problem for drinking water supliers, because: 50 mg l-1 is the upper limit in drinking water

  6. Consequences of N surplus • Soil mineral nitrogen increased • Nitrate leaching increased • Nitrate concentration in groundwater often increased over 50 mg l-1 • Problem for drinking water supliers, because: 50 mg l-1 is the upper limit in drinking water 80 % of the drinking water comes from groundwater

  7. Measures to reduce nitrate leaching • Prevention of overfertilization • Promotion of cover crop cultivation during fall

  8. Result check: Monitoring programs • In drinking water catchments • Soil mineral nitrogen (NO3-N) in 0-90 cm depth • In fall before leaching begins

  9. Result check: Monitoring programs Baden-Württemberg:- Since 1987- First program in Germany- 60000 samples per year

  10. Trend ofsoil mineral nitrogen in Baden-Württemberg

  11. Trend ofsoil mineral nitrogen in Baden-Württemberg

  12. Trend ofsoil mineral nitrogen in Baden-Württemberg

  13. Preliminary result - Soil nitrate concentration decreases- Nitrate leaching probably decreases

  14. Methodical challenges? Are there still problems, that should be solved? Are there anyhow methodical challenges?

  15. Trend ofsoil mineral nitrogen in Baden-Wuerttemberg

  16. Trend ofsoil mineral nitrogen in Baden-Wuerttemberg

  17. Methodical challenge: Quantification of the influences of the weather on the mineral N content of the soils

  18. Result check: Monitoring programs Liebenau- Since 1992- 100 samples per year

  19. Soil mineral nitrogen in Liebenau

  20. Soil mineral nitrogen and the precipitation until sampling date

  21. Soil mineral nitrogen and the precipitation until sampling date

  22. Soil mineral nitrogen and the precipitation until sampling date

  23. Soil mineral nitrogen and the precipitation until sampling date

  24. Soil mineral nitrogen and the precipitation until sampling date

  25. Soil mineral nitrogen as a function of precipitation until sampling date

  26. Soil mineral nitrogen as a function of precipitation until sampling date

  27. Simple regression with 1 variable NO3-N = - 0.15P10 + 66.7 r2 = 0.46* NO3-N = mean NO3-N fall content of all soils (kg ha-1), 0-90 cm depth P10 = Precipitation since 1. October, until date of sampling (mm)

  28. NO3-N = - 0.15P10 + 66.7 r2 = 0.46*

  29. NO3-N = - 0.15P10 + 66.7 r2 = 0.46*

  30. NO3-N = - 0.15P10 + 66.7 r2 = 0.46*

  31. Multiple regression with 2 variables NO3-N = - 0.20P10- 2.8 Y + 86.6 r r2 = 0.86 *** NO3-N = mean NO3-N fall content of all soils (kg ha-1), 0-90 cm depth P10 = Precipitation since 1. October, until date of sampling (mm) Y = Year (1992 = 0; 1993 = 1; 1994 = 2; etc.), temporal trend

  32. Multiple regression with 2 variables NO3-N = - 0.20P10 - 2.8 Y + 86.6 r2 = 0.86 *** NO3-N = mean NO3-N fall content of all soils (kg ha-1), 0-90 cm depth P10 = Precipitation since 1. October, until date of sampling (mm) Y = Year (1992 = 0; 1993 = 1; 1994 = 2; etc.), temporal trend

  33. NO3-N = - 0.20P10 - 2.8 Y + 86.6 r2 = 0.86 ***

  34. Multiple regression with 4 variables NO3-N = - 0.17P10 - 3.2 Y - 0.08 P9 + 3.1 T10 + 52.3 r2 = 0.97 *** NO3-N = mean NO3-N fall content of all soils (kg ha-1), 0-90 cm depth Y = Year (1992 = 0; 1993 = 1; 1994 = 2; etc.), temporal trend P10 = Precipitation since 1. October until date of sampling (mm) P9 = Precipitation of September (mm) T10 = Mean air temperature at 2 p.m. in October (° C)

  35. Multiple regression with 4 variables NO3-N = - 0.17P10 - 3.2 Y - 0.08 P9 + 3.1 T10 + 52.3 r2 = 0.97 *** NO3-N = mean NO3-N fall content of all soils (kg ha-1), 0-90 cm depth Y = Year (1992 = 0; 1993 = 1; 1994 = 2; etc.), temporal trend P10 = Precipitation since 1. October until date of sampling (mm) P9 = Precipitation of September (mm) T10 = Mean air temperature at 2 p.m. in October (° C)

  36. Multiple regression with 4 variables NO3-N = - 0.17P10- 3.2 Y- 0.08 P9 + 3.1 T10 + 52.3 r2 = 0.97 *** NO3-N = mean NO3-N fall content of all soils (kg ha-1), 0-90 cm depth Y = Year (1992 = 0; 1993 = 1; 1994 = 2; etc.), temporal trend P10 = Precipitation since 1. October until date of sampling (mm) P9 = Precipitation of September (mm) T10 = Mean air temperature at 2 p.m. in October (° C)

  37. NO3-N = - 0.17P10 - 3.2 Y - 0.08 P9 + 3.1 T10 + 52.3 r2 = 0.97 ***

  38. Decrease of nitrate in groundwater

  39. Conclusions Preliminary results: - Measures to reduce the nitrate leaching are successful

  40. Conclusions Methodical challenge: - Values of soil nitrate are superimposed by atmospheric influences

  41. Conclusions Methodical challenge: - Values of soil nitrate are superimposed by atmospheric influences - Multiple regression models can detect these influences

More Related