Soil Carbon Sequestration for Climate Change Mitigation …
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soils to atmosphere. This is estimated by 3.5 C Pg annual increase in atmospheric C,
which means that soil acts as a C source and atmosphere acts as a C sink [54, 62].
Forests is important ecosystems, however, over the time, forest surface area has
decreased due to increasing human development. Recently, the attention is paid to
forests not only because its providing of wood products to society in addition to other
important ecosystem services, such as recreation, habitat functions, water regulation,
water erosion control, and improved air quality, but also because of its potentiality
of C sequestration in addition to biomass provision for bioenergy. This also illustrates the possible trade-offs even within the theme of climate change mitigation
[26]. The overall decrease of SOM in croplands has become a threat to soil sustainability. The COP21 conference held in November 2015 in Paris resulted in the
adoption of a “4p1000” initiative aiming at favoring C storage practices to mitigate
greenhouse gas emissions such as recycling of organic waste treatments originating
from urban, industrial, and agricultural activities. This will be a promising source
of C stocking amendments that can also substitute synthetic fertilizers [63]. Therefore, restoration processes and converting agricultural soil to a more natural land use
opposites some of the effects responsible for SOC depletion as a result of the conversion of natural to managed ecosystems. Applying ecological management concepts
to natural resources, such as nutrient cycling, favorable C budget, enhancing soil
biodiversity and soil mixing by macro invertebrates, may be an important factor to
improve soil quality and SOC sequestration [54]. Retention of crop residues, no till
farming and crop cover incorporation in a diversified rotation cycle (i.e. Conservation Agriculture), integrated nutrient management techniques of utilizing compost
and biosolids, erosion control, water conservation, contour hedges with perennials,
controlled grazing etc. are so important techniques of land use and soil management.
Such techniques lead to C sequestration with an average long-term SOC sequestration rate 200–1000 kg/ha/year in humid temperate regions and 50–250 kg/ha/year
for in tropical regions. Also, SIC sequestration rate is about 5–25 kg/ha/year in arid
and semi-arid regions [54].
Hence, understanding the influence of SOC by future climate and land use changes
can help land managers and policymakers to develop appropriate land planning strategies. However, examining multiple scenarios to understand the range of potential outcomes is crucial when assessing future environmental and anthropogenic changes
[32].
7.4 Topography
Topography is one of the key factors of soil formation. The topography (i.e. slope,
position, and topographical direction), associated with elevation [26]. Topography
is one of the most affecting factors on soil C and N contents at the field level.
However, topographical effects are probably differing in magnitude in different agricultural systems [64]. Topography plays an important role in temperature and moisture regimes because of differences in insolation period based on site aspect, which
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soils to atmosphere. This is estimated by 3.5 C Pg annual increase in atmospheric C,
which means that soil acts as a C source and atmosphere acts as a C sink [54, 62].
Forests is important ecosystems, however, over the time, forest surface area has
decreased due to increasing human development. Recently, the attention is paid to
forests not only because its providing of wood products to society in addition to other
important ecosystem services, such as recreation, habitat functions, water regulation,
water erosion control, and improved air quality, but also because of its potentiality
of C sequestration in addition to biomass provision for bioenergy. This also illustrates the possible trade-offs even within the theme of climate change mitigation
[26]. The overall decrease of SOM in croplands has become a threat to soil sustainability. The COP21 conference held in November 2015 in Paris resulted in the
adoption of a “4p1000” initiative aiming at favoring C storage practices to mitigate
greenhouse gas emissions such as recycling of organic waste treatments originating
from urban, industrial, and agricultural activities. This will be a promising source
of C stocking amendments that can also substitute synthetic fertilizers [63]. Therefore, restoration processes and converting agricultural soil to a more natural land use
opposites some of the effects responsible for SOC depletion as a result of the conversion of natural to managed ecosystems. Applying ecological management concepts
to natural resources, such as nutrient cycling, favorable C budget, enhancing soil
biodiversity and soil mixing by macro invertebrates, may be an important factor to
improve soil quality and SOC sequestration [54]. Retention of crop residues, no till
farming and crop cover incorporation in a diversified rotation cycle (i.e. Conservation Agriculture), integrated nutrient management techniques of utilizing compost
and biosolids, erosion control, water conservation, contour hedges with perennials,
controlled grazing etc. are so important techniques of land use and soil management.
Such techniques lead to C sequestration with an average long-term SOC sequestration rate 200–1000 kg/ha/year in humid temperate regions and 50–250 kg/ha/year
for in tropical regions. Also, SIC sequestration rate is about 5–25 kg/ha/year in arid
and semi-arid regions [54].
Hence, understanding the influence of SOC by future climate and land use changes
can help land managers and policymakers to develop appropriate land planning strategies. However, examining multiple scenarios to understand the range of potential outcomes is crucial when assessing future environmental and anthropogenic changes
[32].
7.4 Topography
Topography is one of the key factors of soil formation. The topography (i.e. slope,
position, and topographical direction), associated with elevation [26]. Topography
is one of the most affecting factors on soil C and N contents at the field level.
However, topographical effects are probably differing in magnitude in different agricultural systems [64]. Topography plays an important role in temperature and moisture regimes because of differences in insolation period based on site aspect, which