Nutrient Release Pattern of ... Loam Soils
Physicochemical Properties of initial soil (Table 1)
The soils of the study location varied in their soil
properties, where the pH of both the location was almost
near neutral (6.42 and 6.67). The Electrical Conductivity
(EC) of the soils was 0.08 and 0.09 (dSm -1 ). Based on
the soil test data, both the soil samples were found low in
organic carbon (OC) with 0.33 and 0.29. Regarding B, the
soil available B were 0.28 and 0.26 mg kg -1 respectively
which showed deficient in both the locations.
Boron fractions
The different boron fractions showed an increased trend
with graded levels of boron at field capacity during
the incubation period in the soils of both the locations
Among all the boron fractions, the contribution of the
residual boron to the total boron content was the highest
among all the boron fractions estimated.
Non specifically adsorbed boron (Tables 2 and 3)
Among the different fractions, non specifically adsorbed
boron fraction showed an increasing trend for added
levels of boron compared to control in both soils. At
21 days of incubation, the non specifically adsorbed
boron in soils reached a maximum content (0.62, 0.65,
0.91, 1.03, 1.01 and 0.59, 0.62, 0.88, 1.00, 0.98 mg
kg -1 respectively in both the locations) at B @ 2.0 kg
ha -1 . The highest content of this fraction to total boron
(58.76 and 56.30 and mg kg -1 ) reached a peak with
1.03 and 1.0 mg kg -1 and contributed towards 0.02 and
0.01% of total B, respectively at B @ 2.0 kg ha -1 in
both locations. At 30 days after incubation, the release
pattern of this fraction with the application of B @ 2.0 kg
The various boron fractions were estimated in the soil
ha -1 showed a decreasing trend with a value of 1.01 and
and the results are presented hereunder.
0.98 mg kg -1 in both the locations. During the incubation
period, the non specifically adsorbed boron in soils of
Results and Discussion
both the locations ranged from 0.13 -1 .03 and 0.1 - 1.0
Boron exists in different forms and distinguished in
mg kg -1 and reached the maximum at B @2.0 kg ha -1
many categories. Soil B, as adsorbed by clay minerals,
after 21 days of incubation. This meagre contribution
organic matter, Al and Fe oxides and calcium carbonate
might be due to the low availability of available boron
can be stored or removed depending on changes of boron
in soil under this study. Similar findings also reported by
concentration in soil solution. The various boron fractions
Karthikeyan and Shukla, (2011).
studied were also illustrated graphically in fig. 1 and 2.
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