## 4 Application of Biochar for Remediation of Pesticide-Contaminated Soils  
Biochar can be used in contaminated soils as an amendment and remediating agent to immobilize and reduce the bioavailability and toxicity of pesticides. Applying biochar to agricultural soils has varying impacts depending on the feedstock, pyrolysis temperature, and application rates [110]. Understanding biochar's function in various applications can help develop or choose the best biochar for a given application based on feedstock composition, production parameters, and post-treatment qualities. Addition of biochar to the soil has two roles: it drives contaminants into or adsorbs them onto the biochar, while it can also release nutrients that increase the rate of microbial degradation of the contaminants. Applying biochar to soil can play a significant role in altering nutrient dynamics, soil contaminants, and microbial functions. Biochar improves soil fertility in pesticide-contaminated soils. Certain sorption/deactivation potential (shown by high sorption and low desorption) for pesticides is retained by the biochar after nearly three years in soils. Table 3 demonstrates that biochar can effectively improve soil quality and reduce its ecological risk. \begin{table}
\begin{tabular}{c c c c c c} \hline \begin{table}
\begin{tabular}{c c c c c c} \hline
**Biochar Type** & **Pyolysis Temperature** & **Contimainant (Resticide)** & **Application Effects** & **Active Matrix** & **Reference** \\ \hline  & & & & Not only did the biochar-immobilized WZ-2 speed & \\  & & tebuconazole & tebuconazole breakdown, but it also restored native & soil & [119] \\ wheat straw & 700 \({}^{\circ}\)C & (bactericide) & soil microbial enzyme activity and community & soil & [119] \\  & & & composition. & & \\ rice hull & 600 \({}^{\circ}\)C & & fomesafen & In agricultural soils, biochar additions likely change & \\  & & (herbicide) & the fate of herbicides by reducing their transit via & soil & [120] \\  & & & improved adsorption. & & \\  & & & & be/MDP protected the function and metabolic activity & \\ corn stalk & 600 \({}^{\circ}\)C & & atrazine & of herbical bacteria susceptible to atrazine & \\  & & (herbicide) & contamination during the early stage of pollution, & soil & [121] \\  & & & hence preserving their relative abundance. & \\  & & & & \\  & & & & \\  & & & & \\  & & & & \\  & & & & \\  & & & & \\  & & & & \\  & & & & & \\  & & & & \\  & & & & \\  & & & & \\ \end{tabular}
\end{table} 
Table 3: _Cont._  
\begin{table}
\begin{tabular}{c c c c c c} \hline
**Biochar Type** & **Pyalysis Temperature** & \begin{tabular}{c} **Contaminant** \\ **(Resicide)** \\ \end{tabular}  & **Application Effects** & **Active Matrix** & **Reference** \\ \hline \multirow{4}{*}{eucalyptus origin} & \multirow{4}{*}{400-500 °C} & \multirow{4}{*}{400-500 °C} & \multirow{4}{*}{\ \begin{tabular}{c} düuren \\ (herbicide) \\ \end{tabular}  } & Due to the increased düuron sorption capacity and & \multirow{4}{*}{ \begin{tabular}{c} soll \\ \end{tabular}  } \\  & & & & \\  & & & & \\ \cline{1-  
Insecticides used as chemical growth inducers, increased hormone releases, pesticides, weedicides, and synthetic fertilizers cause environmental issues. The enormous benefits of biochar in agriculture and the environment are coupled with downsides [130]. Illustrating the negative effects of improper biochar usage, using biochar in soil remediation on a large scale may expose animals, plants, microbes, and agricultural crops to harmful effects from the biochar's adsorbed hazardous chemicals. This might have deleterious impacts on the biotic environment. Certain biochars can function well in improving soil, while other biochars cannot [131]. The appropriate modification methods depend on the environmental application [132]. As biochars' properties change over time, the pesticides' application rate might need to be adjusted for different pesticides every cropping season.