**7.3 Enhanced nitrogen fertilizer**

Fertilizers and water need to be supplied increasingly as food and agricultural practices keep increasing. The rate at which population increases demands that more food should be supplied; hence, more fertilizer is needed. Over the years, the supply of nitrogen has been insufficient and mismanaged; thus, there is need to improve the supply of nitrogen and device affordable means of sustaining the

**Figure 4.** *Soil enhancement through biochar addition [35].*

supply [15, 19]. Plants normally do not utilize more than 50% of the soil nitrogen; therefore, adequate technology should be invented in order to build the mechanism that would increase nitrogen uptake in plants. Part of these measures is the introduction of biochar into the soil to encourage the uptake of nitrogen from pure organic sources [18, 30].

The addition of biochar to soil increases the pool of nutrients and the volume of nitrogen available to plants. Organic amendment of soil provides the soil with nutrients like nitrogen, phosphorus and potassium [29, 33–35]. Therefore, biochar addition to the soil enhances improved supply of nutrients to plants and to the soil.

### **7.4 Soil structure improvements of biochar**

Biochar amendments into the soil improves soil's nutrients and structure due to the high porosity of the biochar, leading to the formation of well-structured aggregates that enhances soil's water holding capacity. In tropical regions and areas with low rainfall, the addition of biochar to the soil improves the water retention capacity in the dry season [2, 13, 34]. The tensile strength of the soil increases as a result of accumulation of more organic matter. This forms a strong structure for the plant roots to adhere to. The strong adherence improves the soil ecosystem because the bonding of the soil aggregates prevents erosion and displacement of the top-most layers of the soil [11]. Thus, this overall soil structure improvement proves the evidence of the advantage of the physicochemical attributes of biochar to prevent adverse soil conditions caused by earth's geogenic and climate activities, thereby mitigating climate change [12, 36].

### **7.5 Biochar and mitigation of greenhouse gases**

Biochar possess interesting properties like the presence of high-stable carbon necessary for the carbon capturing. The high stability of biochar carbon therefore gives biochar products an edge over other additives and conditioners. Thus, with the effective sinking of carbon from the soil, it regulates the presence of carbon dioxide in the atmosphere [29, 30]. Likewise, this property of biochar stability increases the turnover rate and half-life of biochar in the soil for more number of years. However, the mitigation of other greenhouse gases other than carbon dioxide by biochar has still not been investigated. Therefore, further research needs to be carried out to evaluate the effectiveness of biochar in regulating other greenhouse gases [33]. Also, effective measures of evaluating the emissions of these gases must be considered with the aim of saving up the greenhouse gases pertaining to the emission trading schemes [17, 18, 37].

Also, the use of plant and animal wastes for biochar is a means of preventing the emission of methane and nitrous oxide gas from landfills, which are potent greenhouse gases.

### **7.6 Biochar in environmental conservation**

Biochars effect in environmental conservation deals with waste management, soil remediation and energy conservation. Animal wastes and biomass from agricultural produce can be processes under certain environmental conditions using pyrolysis [1, 10, 34]. The emission of greenhouse gases from wastes is reduced if the plant and animal biomass is processed into biochar [20].

Another major advantage of biochar for environmental conservation is the use of biochar as renewable fuel. The incineration of carbonized products can be processed into biochar which releases lesser amounts of inorganic materials into the environment because carbonized materials are purely organic [36].

**153**

*Enhancement of Soil Health Using Biochar DOI: http://dx.doi.org/10.5772/intechopen.92711*

production [29].

soil [24, 37].

products yield.

Glomeromycota phyla [25, 38].

tiveness of the biochar [16, 36].

**7.7 Biochar in enhancing soil microbial community**

soil microorganisms after treatment with biochar.

The process of pyrolysis could however alter the extent of release of noncarbon materials like chlorine into the environment. However, the nature of the biomass determines the amount of chlorine released during the process of biomass conversion into biochar during pyrolysis. If the chlorine and other inorganic substances are formed continuously, it leads to the formation of sludge in fuel-burning boilers but with the carbonization of fuel, the sludge formation disappears. Thus, because the carbonization happens inevitably during biochar production, the process of production of biochar is a key process in solving the problem of sludge

Therefore, it is re-iterated that the type, properties and processes of feedstocks used for the formation of biochar is a potent determinant of the nature and effec-

Biochar application to the soil has been found to increase the soil's physicochemical conditions, more especially rate of carbon sequestration and the overall soil fertility [22]. For example, biochar from wood waste was used to amend the soil on which wheat crops were planted in Tuscany, Italy. The soil samples were collected after 3 months of biochar amendment and was analyzed the pH, total organic carbon, microbial biomass, mean substrate-induced respiration and other parameters. It was observed that only the pH and the mean substrate-induced respiration had significant changes after 3 months of amendment, but after 14 months the effect was not pronounced [22, 37]. The result reflects the perking up of the activities of

Furthermore, biochar has an averagely neutral pH ranging from 6.2 to 7.6 (**Table 1**) and majority of microorganisms, especially soil microorganisms thrive well at this pH. Only a few microorganisms are acidophilic and alkanophilic. This therefore increases the chance of more microbial activities in a biochar-amended

Likewise, the porous nature of biochar is obviously an advantage for soil aeration, a good condition for soil aerobes. However, there are also anaerobic organisms (that do not require the presence of oxygen to survive) in the soil. In a condition where the soil aerobes use up the total oxygen in the soil, it provides a good ambience for soil anaerobes to thrive. The porous biochar also increases soil water retention capacity. However, chances of soil water-logging are possible, but the tendency of biochar to form aggregates reduces the chances of soil erosion [38]. The chemical properties of biochar also increase the microbial population in the rhizosphere region of the soil, which is popularly known as the rhizosphere effect [26, 36]. Furthermore, the overall effect of biochar enhances the growth of plants that release vitamins and amino acids from their roots and tissues. These nutrients subsequently increase microbial metabolism and increased microbial

In a biochar-amended tobacco-planting soil in China, rice-straw biochar was used to enhance the soil. Indigenous microorganisms present in the soil were bacteria of the phyla Proteobacteria, Actinomycetes and Acidobacteria; while the predominant fungal phyla were Ascomycota, Zygomycota and Basidiomycota [23, 35]. **Figures 5** and **6** shows that among these groups, only the Actinomycetes

bacteria group and the Ascomycota fungal group respectively reduced in proportion after the addition of biochar while the remaining bacterial and fungal groups increased in proportion after the biochar treatment. Other soil fungal groups that exhibited increased proportion include the Zygomycota and

### *Enhancement of Soil Health Using Biochar DOI: http://dx.doi.org/10.5772/intechopen.92711*

*Applications of Biochar for Environmental Safety*

**7.4 Soil structure improvements of biochar**

**7.5 Biochar and mitigation of greenhouse gases**

trading schemes [17, 18, 37].

**7.6 Biochar in environmental conservation**

plant and animal biomass is processed into biochar [20].

environment because carbonized materials are purely organic [36].

house gases.

organic sources [18, 30].

supply [15, 19]. Plants normally do not utilize more than 50% of the soil nitrogen; therefore, adequate technology should be invented in order to build the mechanism that would increase nitrogen uptake in plants. Part of these measures is the introduction of biochar into the soil to encourage the uptake of nitrogen from pure

The addition of biochar to soil increases the pool of nutrients and the volume of nitrogen available to plants. Organic amendment of soil provides the soil with nutrients like nitrogen, phosphorus and potassium [29, 33–35]. Therefore, biochar addition to the soil enhances improved supply of nutrients to plants and to the soil.

Biochar amendments into the soil improves soil's nutrients and structure due to the high porosity of the biochar, leading to the formation of well-structured aggregates that enhances soil's water holding capacity. In tropical regions and areas with low rainfall, the addition of biochar to the soil improves the water retention capacity in the dry season [2, 13, 34]. The tensile strength of the soil increases as a result of accumulation of more organic matter. This forms a strong structure for the plant roots to adhere to. The strong adherence improves the soil ecosystem because the bonding of the soil aggregates prevents erosion and displacement of the top-most layers of the soil [11]. Thus, this overall soil structure improvement proves the evidence of the advantage of the physicochemical attributes of biochar to prevent adverse soil conditions caused by earth's geogenic and climate activities, thereby mitigating climate change [12, 36].

Biochar possess interesting properties like the presence of high-stable carbon necessary for the carbon capturing. The high stability of biochar carbon therefore gives biochar products an edge over other additives and conditioners. Thus, with the effective sinking of carbon from the soil, it regulates the presence of carbon dioxide in the atmosphere [29, 30]. Likewise, this property of biochar stability increases the turnover rate and half-life of biochar in the soil for more number of years. However, the mitigation of other greenhouse gases other than carbon dioxide by biochar has still not been investigated. Therefore, further research needs to be carried out to evaluate the effectiveness of biochar in regulating other greenhouse gases [33]. Also, effective measures of evaluating the emissions of these gases must be considered with the aim of saving up the greenhouse gases pertaining to the emission

Also, the use of plant and animal wastes for biochar is a means of preventing the emission of methane and nitrous oxide gas from landfills, which are potent green-

Biochars effect in environmental conservation deals with waste management,

agricultural produce can be processes under certain environmental conditions using pyrolysis [1, 10, 34]. The emission of greenhouse gases from wastes is reduced if the

Another major advantage of biochar for environmental conservation is the use of biochar as renewable fuel. The incineration of carbonized products can be processed into biochar which releases lesser amounts of inorganic materials into the

soil remediation and energy conservation. Animal wastes and biomass from

**152**

The process of pyrolysis could however alter the extent of release of noncarbon materials like chlorine into the environment. However, the nature of the biomass determines the amount of chlorine released during the process of biomass conversion into biochar during pyrolysis. If the chlorine and other inorganic substances are formed continuously, it leads to the formation of sludge in fuel-burning boilers but with the carbonization of fuel, the sludge formation disappears. Thus, because the carbonization happens inevitably during biochar production, the process of production of biochar is a key process in solving the problem of sludge production [29].

Therefore, it is re-iterated that the type, properties and processes of feedstocks used for the formation of biochar is a potent determinant of the nature and effectiveness of the biochar [16, 36].

## **7.7 Biochar in enhancing soil microbial community**

Biochar application to the soil has been found to increase the soil's physicochemical conditions, more especially rate of carbon sequestration and the overall soil fertility [22]. For example, biochar from wood waste was used to amend the soil on which wheat crops were planted in Tuscany, Italy. The soil samples were collected after 3 months of biochar amendment and was analyzed the pH, total organic carbon, microbial biomass, mean substrate-induced respiration and other parameters. It was observed that only the pH and the mean substrate-induced respiration had significant changes after 3 months of amendment, but after 14 months the effect was not pronounced [22, 37]. The result reflects the perking up of the activities of soil microorganisms after treatment with biochar.

Furthermore, biochar has an averagely neutral pH ranging from 6.2 to 7.6 (**Table 1**) and majority of microorganisms, especially soil microorganisms thrive well at this pH. Only a few microorganisms are acidophilic and alkanophilic. This therefore increases the chance of more microbial activities in a biochar-amended soil [24, 37].

Likewise, the porous nature of biochar is obviously an advantage for soil aeration, a good condition for soil aerobes. However, there are also anaerobic organisms (that do not require the presence of oxygen to survive) in the soil. In a condition where the soil aerobes use up the total oxygen in the soil, it provides a good ambience for soil anaerobes to thrive. The porous biochar also increases soil water retention capacity. However, chances of soil water-logging are possible, but the tendency of biochar to form aggregates reduces the chances of soil erosion [38].

The chemical properties of biochar also increase the microbial population in the rhizosphere region of the soil, which is popularly known as the rhizosphere effect [26, 36]. Furthermore, the overall effect of biochar enhances the growth of plants that release vitamins and amino acids from their roots and tissues. These nutrients subsequently increase microbial metabolism and increased microbial products yield.

In a biochar-amended tobacco-planting soil in China, rice-straw biochar was used to enhance the soil. Indigenous microorganisms present in the soil were bacteria of the phyla Proteobacteria, Actinomycetes and Acidobacteria; while the predominant fungal phyla were Ascomycota, Zygomycota and Basidiomycota [23, 35]. **Figures 5** and **6** shows that among these groups, only the Actinomycetes bacteria group and the Ascomycota fungal group respectively reduced in proportion after the addition of biochar while the remaining bacterial and fungal groups increased in proportion after the biochar treatment. Other soil fungal groups that exhibited increased proportion include the Zygomycota and Glomeromycota phyla [25, 38].

### **Figure 5.**

*Proportions of soil bacteria after biochar treatment [36]. CK = un-amended treatment; T1 = 2250 kg/ha biochar-amended treatment; T2 = 4500 kg/ha biochar-amended treatment.*

**Figure 6.**

*Proportions of soil fungi after biochar treatment [36]. CK = un-amended treatment; T1 = 2250 kg/ha biocharamended treatment; T2 = 4500 kg/ha biochar-amended treatment.*

### **8. The implications of amending soils with biochar**

Biochar is a natural soil booster and has recorded high success rates over the years in some parts of the world. In some regions including Africa, biochar has been found to yield positive results although some negative results were reported, for example due to improper incorporation of biochar into soil blends which fosters soil erosion [39]. Biochar has been found to balance soil pH, absorb pollutants, improve soil moisture and increases soil aeration. However, there are other economic importance attached with the use of biochar, these include the geographical distribution of the effective use of biochar [38, 39].

Biochar has not been known in some parts of the world due to lack of research, negligence and cultural practices. Another major implication of biochar application is contamination which is of high economic importance. The kinds of cattle manure used in biochar production could be contaminated with non-soil infectious microorganisms, heavy metals or may be denatured due to the high temperature of pyrolysis [40].

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**10. Conclusion**

*Enhancement of Soil Health Using Biochar DOI: http://dx.doi.org/10.5772/intechopen.92711*

ensures overall soil health [40].

soil amendments includes biochar.

**9. Discussion**

constituents. Inadequate improvisation of biochar, for example the use of straw alone, or in inadequate amounts, will also have a negative effect on the soil. Earthworm survival is always put in doubts as well as the soil ecosystem niche that

Soil has been one major source of habitat for plants and animals. However, the anthropogenic activities of humans have contributed to the depletion of natural resources and nutrients from the soil. In a rescue mission to curtail the devastation of land and soil, biochar have been introduced for both agricultural and commercial purposes. Digestion of wastes in less amounts of oxygen at high temperature produces high quality biochar. The high temperature explains the pyrolysis process which is usually more than 200°C anaerobically [4, 41–43]. Biofertilizers and organic fertilizers have served as appetizers to the soil over the years. Recently, other forms of soil amendments have been procured for soil improvement. The soil amendments generally have a low cost and easy accessibility. An example of these

Biochar is environmentally friendly and has a high binding capacity that allows the soil to adhere to biomolecules and absorb nutrients. Biochar is globally known to becoming a means of sustainable amendment of soil and means excavating heavy metals from the soil [44]. Although, biochar is produced from different biomass sources, but biochar produced from carbonization of organic wastes produces amended soil types with high carbon sequestration [45]. The quality of biochar depends on the pyrolysis conditions and raw materials, while the efficiency of biochar not only depends on the pre-production parameters but also the post-production and application procedure of the biochar; which include the type of soil under amendment and the amount of biochar applied [46]. In the process of pyrolysis of biomass, biochar is produced. There are new innovations that need to be applied when producing biochar. For example nanotechnologies and large scale model production are among the recent methods that need to be explored for adequate and mass production of biochar [15, 44, 47]. The temperature of pyrolysis, the particle size and residence time are factors that determine the end product of biomass conversion into biochar. These factors determine the state and half-life of the biochar product [48]. Biochar is a good soil and plant health promoter because it helps to retain the nutrients in the soil through its absorbent power thereby enhancing overall plant growth [49].

The physicochemical property of biochars is key to the enhancement and remediation of the soil. The porous structure and high carbon content are important factors for conservation and sustainability of the soil. A combination of the above properties and the ion-exchange characteristic is symbolic for carbon sequestration, immobilization of heavy metals, and removal of pollutants from the soil [28]. Wastes are used to generate biochars with specific processes like pyrolysis under certain parameters. Biochar is potent enough to trap excess carbon dioxide from the environment but studies have not been seen with regards to mitigating other greenhouse gases. Thus, further research needs to be carried out to evaluate the effectiveness of biochar in regulating other greenhouse gases. Also, effective measures of evaluating the emissions of these gases must be considered with the aim of saving

up the greenhouse gases pertaining to the emission trading schemes.

Excessive removal of feedstock from biochar raw material and production processes could lead to usage of biochar devoid of adequate organic nutrient

constituents. Inadequate improvisation of biochar, for example the use of straw alone, or in inadequate amounts, will also have a negative effect on the soil. Earthworm survival is always put in doubts as well as the soil ecosystem niche that ensures overall soil health [40].
