Fertilizer nitrogen recovery efficiency in the sub-humid highlands of Central Kenya
Material type: TextPublication details: Mexico, DF (Mexico) CIMMYT : 1997ISBN:- 968-6923-93-4
- 633.153 EDM
Item type | Current library | Collection | Call number | Copy number | Status | Date due | Barcode | Item holds | |
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Conference proceedings | CIMMYT Knowledge Center: John Woolston Library | CIMMYT Publications Collection | 633.153 EDM (Browse shelf(Opens below)) | 1 | Available | R624179 |
Nitrogen is one of the major soil nutrients limiting maize production in the sub-humid highlands of Central Kenya. Afield experiment was designed to determine fertilizer N recovery by maize, measured by the 15N isotope technique in two major soil types. Fertilizer N recovery in above-ground parts was low, less than 20% in both soil types. The presence of farmyard manure tended to increase fertilizer N recovery in the acidic andic humic Nitisol but had no effect on fertilizer N recovery in near neutral humic Nitisol. Less than 3% of N applied in the first season was recovered in the second season. There is evidence of N leaching to the lower soil horizons. In the first 0.5 m of top-soil, there was approximately 25 kg N ha-1 in the acidic andic Nitisols, while between 0.5 and 2.5 m there was an accumulation of more than 450 kg N ha-1. In view of low N recovery and high N leaching, it is important to design strategies for more efficient N utilization by maize and recycling of the large quantities of N accumulated in lower soil horizons. Leaching of N to lower soil horizons may be a greater problem than anticipated by researchers and farmers, or conversely may constitute a large reserve of N.
English
9801|AGRIS 9702|anterior|R97-98PROCE|FINAL9798
Jose Juan Caballero
CIMMYT Publications Collection