Book of Extended summaries ISDA

International Conference on Reimagining Rainfed Agro-ecosystems: Challenges &
Opportunities during 22-24, December 2022 at ICAR-CRIDA, Hyderabad
Results
The readily mineralizable carbons (RMC) and microbial biomass carbons (MBC) were
increased from 8 days of treatment imposition to 28 days then decreased at 38 days
irrespective of treatments. The labile carbon and soil enzymatic activities (β-glucosidase,
DHA and FDA) were found higher in IIRS (T1), followed by SRS (T3), ZT (T2) and ZT+SR
(T4) (Table-2). The MBC and RMC values for IIRS, ZT, SRS and ZT+SR treatments were
found to be 338.7, 305.9, 323.5, 285.7 µg Cg -1 and 243.6, 218.3, 230.5, 210 µg Cg -1
respectively. The β-glucosidase activity for IIRS, ZT, SRS and ZT+SR was found to be 14.9,
11.9, 13.9 and 11.1 respectively. FDA and DHA for the same treatments vis-à-vis IIRS, ZT,
SRS and ZT+SR were 4.2, 3.1, 3.7, 2.7 and 122.4, 100.9, 110.8, 94.3 respectively. The
methane emission was higher in IIRS (T1) flowed by SRS (T3), ZT (T2) and ZT+ST (T4)
(Figure 2). The CO2 and CH4 emissions were increased from 3 to 18 days of treatment
imposition and then decreased slowly. The CO 2 and N 2O (Figure 2) emissions trends were
the same. However, in the treatment of IIRS, the methane emission was higher than that of
SRS. All the GHGs (CO 2, CH 4 and N 2O) emissions were relatively less in zero tillage (ZT).
Enzymatic activity details after different treatment imposition
Treatment
Microbial
biomass carbon
(µg C g -1 )
Readily
mineralizable
carbons (µg C
g -1 )
β-
glucosidase
(µg pNP g -
1
h -1 )
Fluorescein
diacetate activity
(µg fluorescein g -
1
h -1 )
Dehydrogen
ase activity
(µg TPF g -1
d -1 )
IIRS 338.7 243.6 14.9 4.2 122.4
ZT 305.9 218.3 11.9 3.1 100.9
SRS 323.5 230.5 13.9 3.7 110.8
ZT+SR 285.7 210.0 11.1 2.7 94.3
Conclusion
In-situ management of straw should be promoted through zero-tillage based practices rather
than direct incorporation in the field as it reduces the GHGs emissions and build labile carbon
pools in the soils during decomposition straw in the field. These practices also have good
climate change mitigation potential.
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