Agriculture Reference
In-Depth Information
The increasing role of groundwater in agriculture has made it very en-
ergy-intensive. Groundwater exploitation has enabled farmers to supple-
ment their irrigation requirements and to cope with the vagaries of the sur-
face supplies. This allows them not only to increase their production level
and incomes but also enhance their opportunities to diversify their income
base and to reduce their vulnerability to the seasonality of agricultural pro-
duction, and to external shocks such as droughts (Bhutta, 2002; Qureshi
et al., 2009). Groundwater use has also increased resilience to climate
change because surface storages have fared poorly on these counts. These
benefi ts will become even more important as climate change heightens
hydrological variability. From society's point of view, aquifer storage is
also advantageous because it minimizes water loss through non-benefi cial
evaporation for semi-arid countries like Pakistan, where surface storages
can lose 3 m or more of their storage every year through pan evaporation
(Shah, 2009).
The introduction of cheap technologies has played a key role in the
groundwater boom in Pakistan. As a result, farmers tend to over-irrigate
and a considerable amount of pumped water evaporates, or goes back to
the aquifer through deep percolation. In both ways, a signifi cant amount of
consumed energy does not contribute to biomass production (Karimi et al.,
2012). Other disadvantages of excessive groundwater use are declining
groundwater tables and increasing salt content in the pumped groundwa-
ter. Groundwater irrigation is also expensive as compared to gravity-run
canal irrigation. Furthermore, groundwater irrigation is also considered an
environmental hazard because the energy used in pumping groundwater
directly contributes to CO
2
discharge (Shah, 2009).
Pakistan is one of the lowest carbon emitters in the world but the in-
creasing use of groundwater for irrigation is putting extra pressure on en-
ergy resources and directly contributes to an increase in CO
2
discharge.
Therefore, productive and effi cient use of groundwater at farms and de-
creasing pumping is benefi cial for stabilizing aquifers and reducing car-
bon emissions, which could be a key climate change adaptation strategy.
This paper estimates the CO
2
emissions as a result of groundwater extrac-
tion and quantifi es reductions in energy consumption and CO
2
emissions
through the adoption of improved irrigation management strategies.
