| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Dep. of Soil Science
Dep. of Crop Science and Plant Ecology, Univ. of Saskatchewan, Saskatoon, SK, Canada S7N OWO
*Corresponding author (vankessel{at}usask.sask.ca)
ABSTRACT
Topography influences the distribution of water and N, thereby exerting an indirect control on N2-fixing activity of legumes. A study was conducted to assess the (i) variability of N2 fixation in pea (Pisum sativum L.) in a rolling field, and (ii) degree of landscape-scale control on N2 fixation. A 90 by 100 m sampling grid, with 10-m spacings, was established in the field. Each sampling point was classified as either footslope or shoulder. The percentage of N derived from the atmosphere (% Ndfa) was estimated using natural 15N abundance and the A-value approaches. Spring soil water content and inorganic N were most concentrated in the footslopes, whereas mean estimates of % Ndfa showed inverted spatial distribution patterns. At flowering, natural 15N abundance estimates of % Ndfa did not differ between shoulders and footslopes. In contrast, A-value mean estimates of % Ndfa were 84% for shoulders and 92% for footslopes. The two approaches gave similar mean estimates of % Ndfa at maturity, with values of approximately 72 and 84% for footslopes and shoulders. A random spatial pattern existed for total aboveground N accumulation, indicating that pea was able to adjust its N2-fixing activity according to the available soil N. Despite similar spatial patterns for % Ndfa estimated using the two approaches, the correlation between the A value and natural 15N abundance approaches was poor (r = 0.213 at flowering and r = 0.377 at maturity). The poor correlation suggests that N2 fixation by pea was partially controlled at the landscape scale, whereas strong micro-scale controls may have existed that ultimately regulated N2 fixation.
Contribution no. R763 of the Saskatchewan Center for Soil Research.
Received for publication September 8, 1994.
This article has been cited by other articles:
|
|
 |
|
  H. R. Kutcher, S. S. Malhi, and K. S. Gill Slope Position, Nitrogen Fertilizer, and Fungicide Effects on Diseases and Productivity of Wheat on a Hummocky Landscape Agron. J., September 19, 2005; 97(5): 1452 - 1459. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. R. Kutcher, S. S. Malhi, and K. S. Gill Topography and Management of Nitrogen and Fungicide Affects Diseases and Productivity of Canola Agron. J., March 1, 2005; 97(2): 533 - 541. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. Locher, H. Heuwinkel, R. Gutser, and U. Schmidhalter Development of Near Infrared Reflectance Spectroscopy Calibrations to Estimate Legume Content of Multispecies Legume-Grass Mixtures Agron. J., January 1, 2005; 97(1): 11 - 17. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 F. Walley, T. Yates, J.-W. van Groenigen, and C. van Kessel Relationships Between Soil Nitrogen Availability Indices, Yield, and Nitrogen Accumulation of Wheat Soil Sci. Soc. Am. J., September 1, 2002; 66(5): 1549 - 1561. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J.-W. van Groenigen and C. van Kessel Salinity-induced Patterns of Natural Abundance Carbon-13 and Nitrogen-15 in Plant and Soil Soil Sci. Soc. Am. J., March 1, 2002; 66(2): 489 - 498. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. Walley, G. Fu, J.-W. van Groenigen, and C. van Kessel Short-Range Spatial Variability of Nitrogen Fixation by Field-Grown Chickpea Soil Sci. Soc. Am. J., November 1, 2001; 65(6): 1717 - 1722. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| The SCI Journals | Agronomy Journal | Crop Science | |||
| Vadose Zone Journal | Journal of Plant Registrations | ||||
| Journal of Natural Resources and Life Sciences Education |
Journal of Environmental Quality |
||||
