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R. R. Shahin
Agricultural soil is an important driver of GHG emissions, depending on soil
type and composition. Emissions from clay soils are higher compared to sandy soils,
especially in presence of high moisture and organic matter contents and high pH
that encourages the increase CO 2 and N 2 O fluxes. Global warming increases carbon dioxide (CO 2 ) emissions with an exponential relationship with increasing the
temperature of the surface layer of agricultural soils. Nitrogen fertilizers are a major
source of N 2 O emissions both in dry soils due to nitrification process or denitrification in waterlogged soils where anaerobic conditions are appropriate for the nitrogen
reduction process. The maximum amount of nitrous oxide is released from the soil
immediately after applying nitrogen fertilizer and for a short period, especially in
the rice fields. The emitted-N 2 O is 14 times at the rate of 210 kg N per ha. Poor
land management by frequent and extensive plowing, excessive fertilization, heavy
irrigation and complete scraping of crop residues promoted GHG emissions from
soils. Rice and wetland farms are the main source of methane emissions due to anaerobic process, accounting for about 20% of the world’s agricultural GHG emissions.
The burning of agricultural waste represents 25% of the total agricultural emissions
Africa. In Egypt, @25 Mt of rice husk and sugarcane wastes are burned in open field,
which contributes strongly to climate change in the near future.
On the other hand, agricultural land is a victim of climate change in direct and
indirect ways. Global warming works to accelerate the burning of organic matter in
the soil, which reduces the fertility of soil, water storage and microbial activity, as it
destroys the texture and increases their susceptibility to soil compaction. Soil compaction induce negative impact on soil water stable aggregates, infiltration, aeration,
root development which increase soil loss through surface sealing, crusting, runoff
and erosion, which leads to deterioration of soil productivity for food. The surface
layer of soil is expected to lose approximately 55 Mt of carbon by the year 2050,
representing about 17% of total expected emissions. Carbon flux is more frequently
higher from the surface layer of soil cultivated than from uncultivated soils. Carbon loss is low and even stored in wetlands, such as in the surrounding areas of the
Manzala and Borolus lakes in northern Delta.
The changes in rainfall and temperature my lead to a considerable shifting in
vegetation pattern which may seriously affect sensitive types of soil flora and fauna
and increased the bacterial to the fungal ratio of the community especially in soils
enriched with organic matter. Global warming generates changes in the pattern of
rainfall. When it decreased, drought dominates the entire area of Egypt and increased
desertification. This is offset by sudden increases in rainfall resulting in heavy floods
that increase surface runoff and erosion. In both cases, large areas of land will lose
their capacity to produce crops.
Global warming induces rising sea level (SLR), which dominates the lowlands.
In Egypt, It is widely assumed that SLR will increase saltwater intrusion processes
in coastal aquifers. The northern delta is one of the most flood-prone areas in the
world. Climate change models showed up to the year 2100 that areas ranging from
1980 to 2870 Km
2 will be submerged by sea water.
Egypt’s agricultural land is experiencing increased drought throughout the country. Northern coasts of the Delta are intruded by rising SLR and salt-affected soils
R. R. Shahin
Agricultural soil is an important driver of GHG emissions, depending on soil
type and composition. Emissions from clay soils are higher compared to sandy soils,
especially in presence of high moisture and organic matter contents and high pH
that encourages the increase CO 2 and N 2 O fluxes. Global warming increases carbon dioxide (CO 2 ) emissions with an exponential relationship with increasing the
temperature of the surface layer of agricultural soils. Nitrogen fertilizers are a major
source of N 2 O emissions both in dry soils due to nitrification process or denitrification in waterlogged soils where anaerobic conditions are appropriate for the nitrogen
reduction process. The maximum amount of nitrous oxide is released from the soil
immediately after applying nitrogen fertilizer and for a short period, especially in
the rice fields. The emitted-N 2 O is 14 times at the rate of 210 kg N per ha. Poor
land management by frequent and extensive plowing, excessive fertilization, heavy
irrigation and complete scraping of crop residues promoted GHG emissions from
soils. Rice and wetland farms are the main source of methane emissions due to anaerobic process, accounting for about 20% of the world’s agricultural GHG emissions.
The burning of agricultural waste represents 25% of the total agricultural emissions
Africa. In Egypt, @25 Mt of rice husk and sugarcane wastes are burned in open field,
which contributes strongly to climate change in the near future.
On the other hand, agricultural land is a victim of climate change in direct and
indirect ways. Global warming works to accelerate the burning of organic matter in
the soil, which reduces the fertility of soil, water storage and microbial activity, as it
destroys the texture and increases their susceptibility to soil compaction. Soil compaction induce negative impact on soil water stable aggregates, infiltration, aeration,
root development which increase soil loss through surface sealing, crusting, runoff
and erosion, which leads to deterioration of soil productivity for food. The surface
layer of soil is expected to lose approximately 55 Mt of carbon by the year 2050,
representing about 17% of total expected emissions. Carbon flux is more frequently
higher from the surface layer of soil cultivated than from uncultivated soils. Carbon loss is low and even stored in wetlands, such as in the surrounding areas of the
Manzala and Borolus lakes in northern Delta.
The changes in rainfall and temperature my lead to a considerable shifting in
vegetation pattern which may seriously affect sensitive types of soil flora and fauna
and increased the bacterial to the fungal ratio of the community especially in soils
enriched with organic matter. Global warming generates changes in the pattern of
rainfall. When it decreased, drought dominates the entire area of Egypt and increased
desertification. This is offset by sudden increases in rainfall resulting in heavy floods
that increase surface runoff and erosion. In both cases, large areas of land will lose
their capacity to produce crops.
Global warming induces rising sea level (SLR), which dominates the lowlands.
In Egypt, It is widely assumed that SLR will increase saltwater intrusion processes
in coastal aquifers. The northern delta is one of the most flood-prone areas in the
world. Climate change models showed up to the year 2100 that areas ranging from
1980 to 2870 Km
2 will be submerged by sea water.
Egypt’s agricultural land is experiencing increased drought throughout the country. Northern coasts of the Delta are intruded by rising SLR and salt-affected soils