Plant and soil Responses to Fertilization of Grasslands in Saskatchewan, Canada and Selenge, Mongolia
Lkhagvasuren, B.. 2007. M.Sc Thesis, Dept. of Soil Science Univeristy of Saskatchewan, Saskatoon, Canada
Abstract
Studies were conducted at three different sites in Saskatchewan, Canada
(Colonsay, Vanscoy and Rosthern) over two years (2005 and 2006) to determine the effect of dribble banded and coulter injected liquid fertilizer
applied in the spring of 2005 at 56, 112 and 224 kg N ha-1
with and without P at 28 kg P2O5ha-1. A similar
study was conducted in 2006 at one site in
Mongolia to determine the effect of
granular N and P fertilizer
application on dry matter yield, and N and P concentration
in plant biomass in the year of application (2006) only. The three Saskatchewan sites
were unfertilized, 7-8 year old stands of mainly meadow bromegrass (Bromus riparius) dominated haylands, while the Mongolia
site was mixed species of native
rangeland.
All fertilization treatments produced significantly (p≤0.05) higher dry matter
yield than the control in the
year of application at the three Saskatchewan sites. The
addition of 28 kg P2O5ha-1
P fertilizer along with the
N fertilizer did not have a
significant effect on yield in most cases. In
the year of application, increasing N rates
above 56 kg N ha-1
did not significantly increase yield over the 56 kg N ha-1
rate in
most cases but did increase N concentration, N uptake and protein content. A
significant residual effect was found in the high N rate treatments in 2006, with
significantly higher yield and N uptake. In
2005, the forage N and P uptake were in
all cases significantly higher than the control in the fertilized treatments. The N
uptake at the three Saskatchewan sites increased with increasing N rate up to the high
rate of 224 kg N ha-1, although the percent recovery decreased with increasing rate.
The P fertilization with 28 kg P2O5ha-1 also increased P uptake at the three
Saskatchewan sites. The site in Mongolia
was less responsive to
fertilization than the
three Saskatchewan sites, with only a significant response in yield, N uptake and no
significant effect of
P fertilization.
