About Us | Help Videos | Contact Us | Subscriptions
 

Abstract

 

This article in JEQ

  1. Vol. 1 No. 3, p. 279-283
     
    Received: Oct 21, 1971


 View
 Download
 Alerts
 Permissions
Request Permissions
 Share

doi:10.2134/jeq1972.00472425000100030015x

Soil Nitrogen Balance in selected Row-Crop Sitesin Southern California1

  1. D. C. Adriano,
  2. F. H. Takatori,
  3. P. F. Pratt and
  4. O. A. Lorenz2

Abstract

Abstract

Nine row-crop sites, where data for nitrogen fertilizer use, crop yields, and amounts of irrigation water used were available for a number of years, were studied to estimate the N balance as related to NO3 in water in the unsaturated zone from below the zone of root influence to the water table or to the 15-m depth.

The system of predicting NO3 concentrations in drainage waters based on the difference between N inputs and N removal in harvested crop sand the drainage volume in which the excess N, converted to NO3, is dissolved, was valid in open-porous soils containing no layers that restrict water movement within the soil profile (0- to 2-m depth). A combination of losses plus net immobilization of up to 56% had to be assumed in some soils to account for all the N loss. In two soils that had been used for disposal of feedlot manure, net mineralization of N from the organic N pool had to be assumed to explain the data obtained.

The current fertilization and irrigation practices used for some row crops in southern California leave varying amounts of NO3 in the drainage water. The amounts depend on the total N added, crop removal, drainage volume, net mineralization, and losses.

  Please view the pdf by using the Full Text (PDF) link under 'View' to the left.

Copyright © .