Rice Production in Egypt: The Challenges of Climate Change …
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sequestration. Paddy fields are documented to have higher SOC storage, and sequestration compared to drier croplands. Organic C accumulation in paddy ecosystems
was faster and more distinct than other arable ecosystems because OM decomposition is reduced in lowland rice fields apparently due to extremely reduced conditions.
As well, the deficiency of oxygen for microbial activity under submerged conditions
results in a decline in the decomposition rate. Incomplete decomposition of organic
materials has been reported in addition to decreased humification of OM under submerged conditions, causing net accumulation of OM in paddy soils. In the long
term, soil management governs the weathering and mineral formation as well as
accumulation of organic nitrogen in paddy soils. The suggested mechanisms for the
accumulation of SOM in paddy soils are known as an occlusion in aggregates, the
formation of organo-mineral associations, the addition of pyrogenic OM [25].
Over recent years, the scarcity and competition for water have been growing
globally, and opportunities for developing new water resources for irrigation became
increasingly limited. Rice as a dominant irrigated crop, representing about 30% of
the total irrigated area. More than 50% of the rice area in the world is irrigated. With
water becoming scarcer, the future of rice production will, therefore, rely heavily
on developing and adopting efficient water use strategies and practices in irrigation
schemes. This situation applies in many parts of the world; however, it is particularly
critical for the Near East region because water is among the most limiting factors for
general development and particularly for agriculture [2].
Rice cultivation is known as an important emitter of greenhouse gases emission
especially methane (as a result of rice management practices, rice straw burning after
harvesting and machinery activities [29]. However, some studies such as [2, 29, 60]
recommended that changing management practices (such as decreasing ploughin,
converting to agriculture conservation, replace burning of rice straw to some other
uses and balanced fertilizer application) will lead to mitigating of greenhouse gases
emission from rice cultivation. As well, such management practices improve buildup of soil organic matter stocks and enhance the environmental impacts of current
management practices.
9 Conclusions
Agricultural soils in North Nile Delta Egypt is vulnerable to water shortage and
climate change. Rice system in this area has higher C and N pools. However the
area of rice production is expected to decline because of many reasons such as
Establishing GERD and climate change. Management practices should be taken into
consideration to avoid such decline in those soils and consequently decline in SOC
which considers one of the most important methods to mitigate climate change if
sequestered in the soil. Sequestering SOC decline CO 2 in the atmosphere where CO 2
is one of the most important GHG that cause climate change. Therefore, the attention
should be paid for soil C sequestration in the North Nile Delta Egypt for balancing
the excepted decline in C and N, due to reducing rice cultivation area because of
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sequestration. Paddy fields are documented to have higher SOC storage, and sequestration compared to drier croplands. Organic C accumulation in paddy ecosystems
was faster and more distinct than other arable ecosystems because OM decomposition is reduced in lowland rice fields apparently due to extremely reduced conditions.
As well, the deficiency of oxygen for microbial activity under submerged conditions
results in a decline in the decomposition rate. Incomplete decomposition of organic
materials has been reported in addition to decreased humification of OM under submerged conditions, causing net accumulation of OM in paddy soils. In the long
term, soil management governs the weathering and mineral formation as well as
accumulation of organic nitrogen in paddy soils. The suggested mechanisms for the
accumulation of SOM in paddy soils are known as an occlusion in aggregates, the
formation of organo-mineral associations, the addition of pyrogenic OM [25].
Over recent years, the scarcity and competition for water have been growing
globally, and opportunities for developing new water resources for irrigation became
increasingly limited. Rice as a dominant irrigated crop, representing about 30% of
the total irrigated area. More than 50% of the rice area in the world is irrigated. With
water becoming scarcer, the future of rice production will, therefore, rely heavily
on developing and adopting efficient water use strategies and practices in irrigation
schemes. This situation applies in many parts of the world; however, it is particularly
critical for the Near East region because water is among the most limiting factors for
general development and particularly for agriculture [2].
Rice cultivation is known as an important emitter of greenhouse gases emission
especially methane (as a result of rice management practices, rice straw burning after
harvesting and machinery activities [29]. However, some studies such as [2, 29, 60]
recommended that changing management practices (such as decreasing ploughin,
converting to agriculture conservation, replace burning of rice straw to some other
uses and balanced fertilizer application) will lead to mitigating of greenhouse gases
emission from rice cultivation. As well, such management practices improve buildup of soil organic matter stocks and enhance the environmental impacts of current
management practices.
9 Conclusions
Agricultural soils in North Nile Delta Egypt is vulnerable to water shortage and
climate change. Rice system in this area has higher C and N pools. However the
area of rice production is expected to decline because of many reasons such as
Establishing GERD and climate change. Management practices should be taken into
consideration to avoid such decline in those soils and consequently decline in SOC
which considers one of the most important methods to mitigate climate change if
sequestered in the soil. Sequestering SOC decline CO 2 in the atmosphere where CO 2
is one of the most important GHG that cause climate change. Therefore, the attention
should be paid for soil C sequestration in the North Nile Delta Egypt for balancing
the excepted decline in C and N, due to reducing rice cultivation area because of