## 3 Results
### Regional Pattern of biogas and compost Potential  
Division-wise biogas and compost production potential against livestock populations are shown in Figure 4. Among the divisions, the highest biogas production of 2690.12 million m\({}^{3}\) (18.72% of the total biogas) was estimated from Rangpur, followed by Rajshahi (2624.07 million m\({}^{3}\)), Chattopram (2161.47 million m\({}^{3}\)), Khulna (2074.01 million m\({}^{3}\)), Dhaka (2006.04 million m\({}^{3}\)), and the Sylhet division has the lowest share (5.66%) of the total biogas potential from livestock manure due to the lower concentration of livestock and poultry in this area. Similarly, the highest compost production potential was found in the \begin{table}
\begin{tabular}{c c c c c c c} \hline
**TN (kgha\({}^{-1}\))** & **TP (kgha\({}^{-1}\))** & **Country** & **Soil Type** & **Crops** & **Others** & **Reference** \\ \hline
9.3 & 0.29 & Finland & Peat soil & Cereals, barley & Subsurface drainage & [80] \\
21.7 & 0.30 & Norway & Mineral soil & Perennial grass & Subsurface drainage & [81] \\
2.41 & 0.64 & China & - & Cereals & Runoff & [82] \\
25 & 0.30 & Finland & Peat soil & Grass & Subsurface drainage & [83] \\
39-191 & 0.9–2.4 & Sweden & & Garden plants & Surface runoff & [84] \\
3.3–30.4 & 0.11–0.32 & Argentina & No-tillage & Cover crops & Rainfall & [85] \\
4.3 & 0.04 & Sweden & Silty loam & Barley, grass & Subsurface & [86] \\
28.5–40.0 & 0.7–4.3 & East Asia & - & Rice, paddy & Subsurface & [87] \\
4.5–12.9 & 0.5–2.6 & East Asia & - & Rice, paddy & Surface runoff & [87] \\ \hline \end{tabular} Note: TN = total nitrogen; TP = total phosphorus.  
\end{table} 
Table 6: Nutrient leaching factors occurring through runoff and subsurface drainage. Rangpur division (12,116.32 kilotons/year), and the lowest compost potential in the Sylhet division (4217.48 kilotons/year). From Figure 4, it is found that the Barisal, Chattogram, and Dhaka divisions had higher livestock populations, but they exhibited comparatively lower biogas or compost potential. Because the number of poultry animals is higher compared to the number of large animals, and poultry produces a lower volume of manure, subsequently, these areas display a low level of biogas and compost production. Similarly, the Rangpur and Sylhet divisions exhibited a higher number of large animals, producing more manure to yield more biogas and compost compared to that of other divisions. District and sub-district-wise biogas and compost production potential from manure in 2024 was presented via spatial analysis (Figures 5 and 6). For annual biogas production among the districts, six districts (Dinaipur, Bogra, Noagano, Sirajgonj, Mymensingh, and Chattogram) were in very high group, with 448.09 to 547.18 million m\({}^{3}\) biogas production potentiality, whereas the other 8, 9, 17, and 24 districts fell into the high (348-448 million m\({}^{3}\)), moderate (249-348 million m\({}^{3}\)), low (150-248 million m\({}^{3}\)), and very low (51-150 million m\({}^{3}\)) groups, respectively (Figure 5a). The sub-districts also displayed the potential for biogas production, which ranged from 9.75 to 109.45 million m\({}^{3}\) per year (Figure 5b). Figure 4: Division-wise biogas and compost potential from livestock manure in 2024: (**a**) total biogas potential (in million m\({}^{3}\)/year); (**b**) total compost potential (in kilotons/year). Figure 5: Total biogas production potential from livestock manure in Bangladesh in 2024: (**a**) district-wise biogas potential; (**b**) sub-district-wise biogas potential. Figure 6: Total compost production potential from livestock manure in Bangladesh in 2024: (**a**) district-wise compost potential; (**b**) sub-district-wise compost potential. The spatial distribution of compost production potential from livestock manure in Bangladesh in 2024 is shown in Figure 6, and the districts are also classified into five categories from very low to very high, based on equal interval classification, similar to those employed for biogas potentiality.