Soil Carbon Sequestration for Climate Change Mitigation …
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and soil erosion prevention. Crop residue is important to soil nutrient cycling and soil
fertility. Crop residue removal will cause the depletion of soil nutrient (e.g. NPK)
which could decline the agronomic productivity and increase soil degradation. Thus,
there are some factors may be considered as limiting factors in the sequestration
process. For example, the removal of crop residue either by burning or by moving
from another place, as well lack the attention of utilizing the organic fertilizers and
manure, the dry climatic conditions which encourage the decomposition of OM, as
well the irrigation does as mentioned above.
Finally; the adoption of good management practices can enhance C and N sequestration. In this context, Wright and Hons [46] motioned that management strategies,
such as no-till and rotations with multiple crops or high-intensity cropping sequences,
play significant roles in SOC and SON sequestration. In this context, they interpreted
lower soil organic nitrogen (SON) storage for continuous soybean systems than for
multiple cropping and double cropping systems which provide greater residue inputs,
by lower crop residue inputs. This may lead to N may not be immobilized to the extent
as would occur under high-intensity cropping, with SON possibly undergoing mineralization and loss from the soil. As well; [46] concluded the enhancement of SOC
and SON sequestration under no-till compared with conventional-tillage
It is worth noticing after presenting the results from the sequestration concept
point of view that the Nile Delta region is one of the most fertile areas of the world.
However; there were some negative changes in this region such as what explained
by [100]. They reported that elevated soil salinity level is one of the principal causes
of reduced agricultural productivity in the Delta. Agricultural management practices
have been changed after the construction of the Aswan High Dam in 1964, also, perennial, furrow irrigation replaced basin flooding, and insensitive cropping replaced the
single crop per year leading to shorter fallow periods. Soil nutrients declined as a
result of intensive cultivation along with a lack of regular nutrient replacement and
a loss of the alluvium deposits. Also, in some areas, overirrigation combined with
insufficient drainage led to increased soil salinity and elevated water tables. Although
these changes, there is a potential opportunity to enhance and sustain agricultural
soil in Egypt especially in Nile Delta and enhancing C and N sequestration through
land use and management practices. In this context Wu et al. [18] mentioned that soil
C increases linearly with increased additions of crop residues and root OM, however,
suggesting that irrigated agriculture will increase soil C with time. It is typical that
SOC commonly declines at the early stages, approaches a steady state in 25–50 year,
and shows an evident increase in about 50 year after native soil conversion to agricultural ones. This pattern suggests that time is an important factor for C sequestration
in irrigated cropland [18]. Thus, understanding the effects of agricultural management on SC stocks and dynamics under specific soil-climatic conditions is warranted
by the necessity of sequestering atmospheric C in agricultural soils to mitigate the
climate change. Adoption of sustainable agricultural practices (e.g., conservation
tillage, residue retention, and using animal or green manure) can increase SOC concentration and enhance soil quality. Reduced tillage practices such as no-till and
chisel till may increase both concentration and amount of SOC in topsoil. However,
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and soil erosion prevention. Crop residue is important to soil nutrient cycling and soil
fertility. Crop residue removal will cause the depletion of soil nutrient (e.g. NPK)
which could decline the agronomic productivity and increase soil degradation. Thus,
there are some factors may be considered as limiting factors in the sequestration
process. For example, the removal of crop residue either by burning or by moving
from another place, as well lack the attention of utilizing the organic fertilizers and
manure, the dry climatic conditions which encourage the decomposition of OM, as
well the irrigation does as mentioned above.
Finally; the adoption of good management practices can enhance C and N sequestration. In this context, Wright and Hons [46] motioned that management strategies,
such as no-till and rotations with multiple crops or high-intensity cropping sequences,
play significant roles in SOC and SON sequestration. In this context, they interpreted
lower soil organic nitrogen (SON) storage for continuous soybean systems than for
multiple cropping and double cropping systems which provide greater residue inputs,
by lower crop residue inputs. This may lead to N may not be immobilized to the extent
as would occur under high-intensity cropping, with SON possibly undergoing mineralization and loss from the soil. As well; [46] concluded the enhancement of SOC
and SON sequestration under no-till compared with conventional-tillage
It is worth noticing after presenting the results from the sequestration concept
point of view that the Nile Delta region is one of the most fertile areas of the world.
However; there were some negative changes in this region such as what explained
by [100]. They reported that elevated soil salinity level is one of the principal causes
of reduced agricultural productivity in the Delta. Agricultural management practices
have been changed after the construction of the Aswan High Dam in 1964, also, perennial, furrow irrigation replaced basin flooding, and insensitive cropping replaced the
single crop per year leading to shorter fallow periods. Soil nutrients declined as a
result of intensive cultivation along with a lack of regular nutrient replacement and
a loss of the alluvium deposits. Also, in some areas, overirrigation combined with
insufficient drainage led to increased soil salinity and elevated water tables. Although
these changes, there is a potential opportunity to enhance and sustain agricultural
soil in Egypt especially in Nile Delta and enhancing C and N sequestration through
land use and management practices. In this context Wu et al. [18] mentioned that soil
C increases linearly with increased additions of crop residues and root OM, however,
suggesting that irrigated agriculture will increase soil C with time. It is typical that
SOC commonly declines at the early stages, approaches a steady state in 25–50 year,
and shows an evident increase in about 50 year after native soil conversion to agricultural ones. This pattern suggests that time is an important factor for C sequestration
in irrigated cropland [18]. Thus, understanding the effects of agricultural management on SC stocks and dynamics under specific soil-climatic conditions is warranted
by the necessity of sequestering atmospheric C in agricultural soils to mitigate the
climate change. Adoption of sustainable agricultural practices (e.g., conservation
tillage, residue retention, and using animal or green manure) can increase SOC concentration and enhance soil quality. Reduced tillage practices such as no-till and
chisel till may increase both concentration and amount of SOC in topsoil. However,