Premium
The Movement of Water and Nitrate Around Bands of Sodium Nitrate in Soils and Glass Beads
Author(s) -
Burns G. R.,
Dean L. A.
Publication year - 1964
Publication title -
soil science society of america journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.836
H-Index - 168
eISSN - 1435-0661
pISSN - 0361-5995
DOI - 10.2136/sssaj1964.03615995002800040008x
Subject(s) - soil water , water content , moisture , leaching (pedology) , chemistry , water table , drop (telecommunication) , nitrate , capillary action , soil science , environmental science , groundwater , materials science , geotechnical engineering , geology , composite material , telecommunications , organic chemistry , computer science
The movement of water and nitrate (NO 3 ‐ ) around bands of NaNO 3 was studied in soils and glass beads in the laboratory. A hypothesis was developed and tested concerning the predominantly downward movement of NO 3 ‐ from a band of NaNO 3 in soils with moisture contents greater than field capacity. The hypothesis of events is as follows: Soil water moves, under the osmotic force generated, to the band of NaNO 3 ; then the NaNO 3 dissolves and diffuses away from the band. However, the effect of the diffusion is reduced when sufficient mobile water is present in the surrounding soil to maintain the influx of water. As a result, the NaNO 3 solution accumulates in the vicinity of the band. Once the accumulating solution exceeds that which can be held by the capillary forces of the soil, the excess NaNO 3 solution literally drops out of the band under the force of gravity. The drop‐out of NaNO 3 solution continues until essentially all of the NaNO 3 has been dissolved. This drop‐out phenomenon occurred in systems in which the water was present initially in quantities greater than field capacity, was moved through the system by leaching, or was moved into the system by capillarity from a shallow water table. Evidence supporting the details of the hypothesis resulted when various shields were used to alter the NO 3 ‐ movement around the fertilizer bands under the leaching and “static” moisture conditions.