Banira Lombardi
“Can pasture type
influence nitrous oxide
emissions from cattle manure?”

Tropical grasses and cattle excreta
Byrnes et al., (2017) demonstrated a reduction in N2O
emissions from cattle urine deposited on tropical grasses
with high BNI capacity.
CH4 CH4
N2O CH4
Tropical pastures with high
BNI capacity reduce N2O
emissions from deposited
manure.
Some tropical pastures have the capacity of
reducing N2O emissions through a Biological
Nitrification Inhibition (BNI) process.
Can pasture type influence gas
emissions from cattle manure?

Site and Gas measurement
Experimental Site
Brachiaria Hybrid
cv. Mulato (BHM)
Brachiaria Humidicola
679 cv. Tully (B679)
High BNILow BNI
Gas measurement
“Closed chamber technique”
(2 manure chamber + 1 control) x 3 parcel x 2 treatments
Gas monitoring was
made during 51 days in a
dry season.
CH4, N2O and CO2
emissions were quantified

Manure and Soil parameters
Mineral Nitrogen Cycle
Potential Nitrification Rate
Incubation assay
NH4
+ and NO3
-
Dynamics of microbial abundance
(qPCR) nitrifier archaea and bacteria
Macrofauna
Total Carbon and Nitrogen on manure and soil

Results
Nitrification rates, microbial
activity and macrofauna are
still in analysis.
At the beginning, ammonium
was greater on manure than
soil. Then the concentration
decreases.
Nitrates on manure increased,
indicating that nitrification is
happening.

Results
What would happen
in wet conditions??
CO2, CH4 and N2O were similar among treatments
N2O
CH4
N2O
Mulato Tully
High BNILow BNI
EFN2O lower than the IPCC default value.

Conclusions
Tropical pastures with BNI
capacity represent a low-
emissions technology that
can play a key role in
mitigating N2O emissions
from cattle manure, especially
under wet conditions.
More studies will be needed,
evaluating the effect of
quantity and quality of
manure and environmental
conditions.

An incredibly enriching experience
Be prepared to develop your personal skills of
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different workplace.
Enjoy it! It is one of the best
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in a PhD training!
Now I am back home, with
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Thanks CLIFF-GRADS Program!!