**3. Organic amendments**

#### **3.1. Animal manure**

by crop residues which suggests the substitution of SOM by fresh SOC derived from crop residues from 3.5 to 5.5 Mg C ha−1 [54]. The use of crop residue as a source of CS and keeping the soil in good quality helps in nutrient management and conservation. In the USA, a total of 367 × 10<sup>6</sup> Mg year−1 crop residues from 9 cereal crops, 450 × 10<sup>6</sup> Mg year−1 for 14 cereals and legumes and 488 × 10<sup>6</sup> Mg year−1 for 21 crops are produced. The amount of total crop residue production in the world is 2802 × 10<sup>6</sup> Mg year−1 from cereal crops and 3758 × 10<sup>6</sup> Mg year−1 from 27 food crops which can sequester 40–60% of total agricultural C emissions through

Biological CS is accomplished by microbial activities. Mechanisms of CS by microbes need to be developed based on experiments and field investigations to predict the CS potential and C cycling under potential global change scenarios [56, 57]. Microbes improve the physical, chemical and biological soil properties in RT or NT areas. The evaluation of the soil microbial and biochemical environment greatly in these areas aids predictions of C availability in soil and plants to quantify CS. Where microbial communities are higher, C and N were 1.32–1.82 [58, 59]. Carbon sequestration was recorded higher up to 49.9 g C kg−1 in soils which were rich

The use of cover crops for the maintenance and restoration of SOM and soil productivity is a popular option [61]. Planting cover crops is a promising option to sequester C in cropping systems by the implementation of recommended management practices. The highest CS rate up to 5.3 t C ha−1 yr.−1 is observed by cover cropping of olive orchards, vineyards and almond orchards. Soil CS rate tends to be the highest during the first years after the change of the management and progressively attains equilibrium. Soil CS rates in cover cropping are much higher than that of fields with low or no cover cropping which suggests that the adoption of

Rice-fallow-rice is one of the dominant cropping systems which has received attention to improve SOM by using organic amendments. Understanding the contributions of organic amendments in CS is important for the estimation of CS, their nutrient supply potential and their role in it. In different organic amendments, poultry manure is found to be more efficient in increasing C and other nutrients in soils and microbial activities which contribute to CS in the rice-rice cropping system [63, 64]. Raw adzuki bean (*Vigna angularis* (Willd.) Ohwi and Ohashi) and wheat (*Triticum aestivum* L.) straw residues can supply C into fields by 499 ± 119 kg C ha−1 [65]. The Mekong Delta, Vietnam, produces 21 Mt. of rough rice (*Oryza sativa* L.) and an estimated 24 Mt. of rice straw annually. The spread of these crop residues in this area can increase CS and SOM, significantly reducing GHG emissions [66].

cover cropping is a sustainable and efficient measure to mitigate CC [62].

Crop residue decomposition acceleration can enhance the SOM [67].

their incorporation in the fields [55].

22 Carbon Capture, Utilization and Sequestration

in soil microbes like fungi and soil bacteria [60].

**2.7. Soil biota management**

**2.8. Cover crops**

**2.9. Soil fertility management**

Animal manure is the source of C and the addition of animal manure to different crop fields has impacts on C contents [68]. Different researchers conducted the experiments in Germany to check the soil's C levels. The experiment showed that the annual application rate of 200 Mg ha−1 yr.−1 of manure to the crop field shows a high level of SOM with respect to adjacent fields [69]. Powlson reported that the mean annual SOC sequestration rates of three long-term (>49) years of manure applications ranged from 10 to 22 kg C ha−1 yr.−1 t −1 of dry solids, while SOC sequestration rates with shorter-term experiments (8–25 years of farmyard manure, cattle slurry and boiler litter) were from 30 to 200 kg C ha−1 yr.−1 t −1 of dry solids [70]. The experiment was conducted to improve the soil quality and crop productivity. Improved soil properties refer to better C management. Animal manure also increases the salt concentration of the soil. The long-term application of manure increases the SOM significantly [71]. In another study, the farm yard manure was applied to the rice-wheat cropping system with NPK fertilizers and results showed significantly an increase in C sequestration in farm yard manure-applied plots than NPK-applied plots [72]. The same experiment was conducted on the maize-wheat cropping system, but in this experiment, the farm yard manure is applied with green manure and indicates that green manure sequesters more C [73]. It was also observed that the high application of N has the potential to sequester C almost at the rate of 1.0–1.4 Mg ha−1 yr.−1 [74].

## **3.2. Crop residues**

The researchers investigated that the annual production of crop residues is about 3.4 × 10<sup>9</sup> tones worldwide. If 15% of the total residue is applied to the soil, it will increase the C contents of soil. The crop residues are the remains of the agricultural crops. The intensive agriculture system increases the crop residue production significantly. This may increase the SOM and soil aggregation and hence C storage [75]. The degradation of crop residue depends upon its composition. For example, it is difficult for microorganisms to start the degradation of the substances which contain a high content of lignin. There three mechanisms, which are classified by different researchers based on the stabilization of SOM, include chemical, biochemical and physical stabilization [76]. Agricultural practices such as the addition of crop residues increase the SOM as well as nutrients contents in the soil by integrated nutrient management [77]. Most studies focus on the fact that the change of crop residue traits has positive effects of the soil CS in organic farming system [78].

#### **3.3. Composting**

Composting is the systematic and controlled breakdown of different types of organic matter including animal manure, woody material and other organic waste. The C content is available in the form of plant uptake in the composting. When the compost matures, 50% of C is available in the form of humic substances [79] and is thought to be more stable practically [80]. In the long-term application of compost, about 8 years or 5 years, a mean 60 kg C ha−1 yr.−1 t −1 of dry solids were monitored [81]. The compost applied in different plots and the soil organic C stock increased significantly compared with the initial stock [82]. It is a win-win condition to increase C storage in the soil as well as plant growth and yield by chemical fertilization. The compost application at the rate of 10 Mg ha−1 yr.−1 results in higher CS. This clear cut indicates that composting not only increases the net primary production but also the C content of the soil [83].

microbial attack and hence when applied to the soil will remain stable for thousands of years

long-term benefits including increase in soil pH [93], increases in crop yield, maintaining the cation exchange capacity, nutrient retention and water-holding capacity. Biochar also reduces the emissions of others greenhouse gases like methane and nitrous oxides [94]. Increased concentration of nitrogen oxides in the atmosphere affects the plant growth by necrosis, slow photosynthetic rate and increased sensitivity of the plants. Gases usually affect the plants by entering them through the stomata of plants [95]. The B has been classified into two classes on the basis of degradation. Class 1 has the potential to store C in soil to about 21.3% and class 2 has potential of about 32.5%. The presence of alkali metals in the B reduces their stability.

the application of B to soil is profitable amendments if the B price is low enough [97]. The response of B at different pH levels was investigated and found that acidic medium emits more carbon dioxide than the alkaline medium. The enhancement of copiotrophic bacteria like gemmatimonadetes and bacteroidetes and the decrease of oligotrophic bacteria increase the C emission in the acidic medium of soil [98]. Biochar-based C management networks have

The studies in China indicate that cultivated and forest soils have the CS potential around 38.5–77 Mt., respectively [107, 108]. The research shows that due to the increase of tempera-

In Belgium in different studies, the C stock was found to be around 319 Mt. and this is due to the increase in mean elevation from Northeast coast to Southeast, and as a result, it leads to a decrease in temperature and an increase in precipitation. Carbon stock is higher in Southeast than Northeast. The C contents in topsoil were found to be 48 t C ha−1 in Luvisols while 113 t

**Strategy Area CS rate (t C ha− 1) Observational time Reference** Organic manure China 0.62 14–40 y [100]

Animal manure Belgium 0.45 20 y [102] Fertilizer plus crop residues Indonesia 0.52 ± 0.16 40 y [103] Inorganic fertilizers South Korea 0.32 ± 0.29 8 y [103] Different crop residues Nigeria 0.24 18 y [104] Crop stubbles Australia 0.19 ± 0.08 — [105] Inorganic fertilizer South Korea 0.32 ± 0.29 8 y [103] Crop residue Nigeria 0.24 18 y [104] Crop stubbles retention Australia 0.19 ± 0.08 4–40 [105, 106]

China 0.62–0.69 03–25 y [101]

the potential to mitigate CC but the quality of B should be appropriate [99] (**Table 2**).

ture from South to North, there is also a decrease of soil organic carbon (SOC) [109].

yr.−1 in soils over long time use [96]. The findings suggest that

Enhancing Carbon Sequestration Using Organic Amendments and Agricultural Practices

[92]. It has

25

http://dx.doi.org/10.5772/intechopen.79336

and thus reduce the release of terrestrial C to the atmosphere in the form of CO2

The B can store 0.55 Pg CO2

C ha−1 in Cambisols soil types [110].

**Table 2.** Different strategies and their carbon sequestration potential.

Organic matter plus in-organic

fertilizer

#### **3.4. Bagasse**

The application of different types of biomass in soil is the best technique to enhance CS in the agricultural sites. The application of bagasse as a biomass in the field showed that bagasse has the potential to sequester C at about 1200–1800 t C year−1 [84]. The application of biochar produced from bagasse is a very authentic organic amendment to soil for retaining its water content [85]. Another study suggested that Bagasse can be converted into B and applied in the soil and it has the potential to sequester C. The porous and high surface area is efficient for the sequestration of C from the atmosphere. Bagasse (B) produced at 600°C showed the most adsorption of C (73.55 mg g−1 at 25°C) [86]. The use of bagasse ash is investigated in an experiment. Different ashes like bagasse and rice husk ash were investigated on wheat soil and the soil organic C content and enzymatic activity were monitored. Bagasse ash increases the soil organic contents at the rate of 525 kg ha−1 y−1 while rice husk ash has no increase of SOM. Bagasse ash increases the soil dehydrogenase and cellulose activity. Long-term investigations are needed to check the effect of ash effects on the soil's physical, chemical and biological properties [87].

#### **3.5. Wood chips**

The world is under threat due to drastic effects of CC, energy access and availability of food. Wood is mostly used as a fuel to cook food and considered as a renewable energy source. Bamboo plantation can sequester C and fix it by producing high biomass. This biomass can be used to generate chips and pellets and as the alternative of fuel; as a result, it can sequester approximately 1.78 kg of C [88]. Another research was conducted and wood chips and straw were applied in the soil and the results showed that nitrogen mineralization and nitrification rates were higher significantly in the soil-applied wood chips. The bad thing is that when we applied wood chips in the soil, nitrogen deficiency occurs and then an additional supplement of nitrogen is required [89]. Carbon contents of early woods are higher than late woods [90]. It is produced from wood-based biomass at a low pyrolysis temperature (400°C) suitable for enhancing the cation exchange capacity, whereas B produced from wood-based biomass at a high pyrolysis temperature (800°C) can enhance nitrate adsorption [85].

#### **3.6. Biochar**

Biochar (B) is usually obtained by the breakdown of crop residues, wood chips, at a low temperature range (350–600°C) in the atmosphere having very little or no oxygen. If the condition remained optimum during the process of B formation including temperature and oxygen, then almost >50% of the C is retained by the B with respect to original biomass [91]. It is resistive to microbial attack and hence when applied to the soil will remain stable for thousands of years and thus reduce the release of terrestrial C to the atmosphere in the form of CO2 [92]. It has long-term benefits including increase in soil pH [93], increases in crop yield, maintaining the cation exchange capacity, nutrient retention and water-holding capacity. Biochar also reduces the emissions of others greenhouse gases like methane and nitrous oxides [94]. Increased concentration of nitrogen oxides in the atmosphere affects the plant growth by necrosis, slow photosynthetic rate and increased sensitivity of the plants. Gases usually affect the plants by entering them through the stomata of plants [95]. The B has been classified into two classes on the basis of degradation. Class 1 has the potential to store C in soil to about 21.3% and class 2 has potential of about 32.5%. The presence of alkali metals in the B reduces their stability. The B can store 0.55 Pg CO2 yr.−1 in soils over long time use [96]. The findings suggest that the application of B to soil is profitable amendments if the B price is low enough [97]. The response of B at different pH levels was investigated and found that acidic medium emits more carbon dioxide than the alkaline medium. The enhancement of copiotrophic bacteria like gemmatimonadetes and bacteroidetes and the decrease of oligotrophic bacteria increase the C emission in the acidic medium of soil [98]. Biochar-based C management networks have the potential to mitigate CC but the quality of B should be appropriate [99] (**Table 2**).

long-term application of compost, about 8 years or 5 years, a mean 60 kg C ha−1 yr.−1 t

**3.4. Bagasse**

24 Carbon Capture, Utilization and Sequestration

biological properties [87].

**3.5. Wood chips**

**3.6. Biochar**

solids were monitored [81]. The compost applied in different plots and the soil organic C stock increased significantly compared with the initial stock [82]. It is a win-win condition to increase C storage in the soil as well as plant growth and yield by chemical fertilization. The compost application at the rate of 10 Mg ha−1 yr.−1 results in higher CS. This clear cut indicates that composting not only increases the net primary production but also the C content of the soil [83].

The application of different types of biomass in soil is the best technique to enhance CS in the agricultural sites. The application of bagasse as a biomass in the field showed that bagasse has the potential to sequester C at about 1200–1800 t C year−1 [84]. The application of biochar produced from bagasse is a very authentic organic amendment to soil for retaining its water content [85]. Another study suggested that Bagasse can be converted into B and applied in the soil and it has the potential to sequester C. The porous and high surface area is efficient for the sequestration of C from the atmosphere. Bagasse (B) produced at 600°C showed the most adsorption of C (73.55 mg g−1 at 25°C) [86]. The use of bagasse ash is investigated in an experiment. Different ashes like bagasse and rice husk ash were investigated on wheat soil and the soil organic C content and enzymatic activity were monitored. Bagasse ash increases the soil organic contents at the rate of 525 kg ha−1 y−1 while rice husk ash has no increase of SOM. Bagasse ash increases the soil dehydrogenase and cellulose activity. Long-term investigations are needed to check the effect of ash effects on the soil's physical, chemical and

The world is under threat due to drastic effects of CC, energy access and availability of food. Wood is mostly used as a fuel to cook food and considered as a renewable energy source. Bamboo plantation can sequester C and fix it by producing high biomass. This biomass can be used to generate chips and pellets and as the alternative of fuel; as a result, it can sequester approximately 1.78 kg of C [88]. Another research was conducted and wood chips and straw were applied in the soil and the results showed that nitrogen mineralization and nitrification rates were higher significantly in the soil-applied wood chips. The bad thing is that when we applied wood chips in the soil, nitrogen deficiency occurs and then an additional supplement of nitrogen is required [89]. Carbon contents of early woods are higher than late woods [90]. It is produced from wood-based biomass at a low pyrolysis temperature (400°C) suitable for enhancing the cation exchange capacity, whereas B produced from wood-based biomass at a

Biochar (B) is usually obtained by the breakdown of crop residues, wood chips, at a low temperature range (350–600°C) in the atmosphere having very little or no oxygen. If the condition remained optimum during the process of B formation including temperature and oxygen, then almost >50% of the C is retained by the B with respect to original biomass [91]. It is resistive to

high pyrolysis temperature (800°C) can enhance nitrate adsorption [85].

−1 of dry

The studies in China indicate that cultivated and forest soils have the CS potential around 38.5–77 Mt., respectively [107, 108]. The research shows that due to the increase of temperature from South to North, there is also a decrease of soil organic carbon (SOC) [109].

In Belgium in different studies, the C stock was found to be around 319 Mt. and this is due to the increase in mean elevation from Northeast coast to Southeast, and as a result, it leads to a decrease in temperature and an increase in precipitation. Carbon stock is higher in Southeast than Northeast. The C contents in topsoil were found to be 48 t C ha−1 in Luvisols while 113 t C ha−1 in Cambisols soil types [110].


**Table 2.** Different strategies and their carbon sequestration potential.

It was found by Indonesian scientists that total SOM was higher if the high clay and silt content was found in soil. The other factors like low pH, rainfall and higher altitude were found responsible for higher soil organic content. The organic content of peatland soil was estimated to be about 33.7 Gt of the 20.9 M ha area of peat soils [111].

ZT zero tillage

N nitrogen

Muhammad Mahroz Hussain

**Author details**

**References**

CoT conventional tillage

SOC soil organic carbon

CA conservation agriculture

\*Address all correspondence to: cmsuaf@gmail.com

Ecosystems & Environment. 2003;**99**:15-27

potential. Global Change Biology. 2000;**6**:317-327

Springer Netherlands; 2004. pp. 281-295

ronment International. 2005;**31**:575-584

Ecosystems & Environment. 2002;**91**:217-232

Zia Ur Rahman Farooqi, Muhammad Sabir\*, Nukshab Zeeshan, Khurram Naveed and

Institute of Soil and Environmental Sciences, University of Agriculture, Faisalabad, Pakistan

Enhancing Carbon Sequestration Using Organic Amendments and Agricultural Practices

http://dx.doi.org/10.5772/intechopen.79336

27

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Agricultural land of South Korea is about 174 Mt. (1 m depth) for the storage of carbon. Soil organic carbon stocks in grass and agricultural lands were as large as 88 and 68 t C ha−1, respectively [112].

A study in Nigeria also revealed that 20-60 t ha-1 is found in top 0.3 m soil layer and a total of 118 Mg C ha-1 can be found in the top 1 m. Humid forest zone contains more C than any other zone [113], and the C stock of Australian topsoils was found to be around 25 Gt because of great land mass as well as low temperature [114].
