TITLE:
Root zone soil moisture redistribution in maize (Zea mays L.) under different water application regimes
AUTHORS:
John Mthandi, Fedrick C. Kahimba, Andrew K. P. R. Tarimo, Baanda A. Salim, Maxon W. Lowole
KEYWORDS:
Soil Moisture Content; Full Crop Water Requirement Regime; Maize Root Zone
JOURNAL NAME:
Agricultural Sciences,
Vol.4 No.10,
September
27,
2013
ABSTRACT: Soil moisture availability to plant roots is very important for crop
growth. When soil moisture is not available in the root zone, plants wilt and
yield is reduced. Adequate knowledge of the distribution of soil moisture within crop’s
root zone and its linkage to the amount of water applied is very important as
it assists in optimising the efficient use
of water and reducing yield losses. The study aimed at evaluating the
spatial redistribution of soil moisture
within maize roots zone under different irrigation water application
regimes. The study was conducted during two irrigatation seasons of 2012 at Nkango
Irrigation Scheme, Malawi. The trials consisted of factorial arrangement in a
Randomised Complete Block Design (RCBD). The factors were water and nitrogen and both were at four levels. The Triscan Sensor
was used to measure volumetric soil moisture contents at different
vertical and lateral points. The study
inferred that the degree of soil moisture loss depends on the amount of water
present in the soil. The rate of soil moisture loss in 100% of full water
requirement regime (100% FWRR) treatment was higher than that in 40% FWRR
treatment. This was particularly noticed when maize leaves were dry. In 100%
FWRR treatment, the attraction between water and the surfaces of soil particles
was not tight and as such “free” water was lost through evaporation and deep percolation, while in 40% FWRR, water was strongly
attracted to and held on the soil particles surfaces and as such its potential
of losing water was reduced.