## 3 Results
### Effects of Fiber Length and Content on Soil Properties Under Two Soil Conditions  
#### 3.1.1 Physical Properties  
As shown in Tables 4 and 5, the addition of fibers significantly increased the total porosity and aeration porosity in both soil types. For Soil-type A, the optimal improvement was observed at a 3 cm fiber length with 0.2% and 0.4% content values, whereas for Soil type B, the 4 cm fiber length exhibited the best performance. The aeration porosity initially increased and then decreased, reaching its highest values at 3 cm + 0.6% and 4 cm + 0.4% combinations. The capillary porosity showed a slight decrease, with the lowest value observed in the 5 cm + 0.6% combination. Fiber incorporation also led to a significant reduction in soil bulk density, with Soil-type A exhibiting the lowest bulk density at a 1-2 cm fiber length and 0.6% content, while Soil-type B showed the lowest value at a 5 cm fiber length and 0.2% content. The hydraulic conductivity increased significantly with higher fiber content, reaching its maximum at a 5 cm fiber length and 0.6% content, with values of 0.78 mm/min for Soil-type A and 0.69 mm/min for Soil-type B. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \begin{tabular}{c} **Fiber** \\ **Content** \\ \end{tabular} & \begin{tabular}{c} **Fiber** \\ **Length** \\ \end{tabular} & \begin{tabular}{c} **Total Porosity** \\ **(\%)** \\ \end{tabular} & \begin{tabular}{c} **Aeration** \\ **Porosity** \\ **(\%)** \\ \end{tabular} & \begin{tabular}{c} **Capillary** \\ **Porosity** \\ **(\%)** \\ \end{tabular} & \
\begin{tabular}{c} **Bulk Density** \\ **(g/cm3)** \\ \end{tabular} &
\begin{tabular}{c} **Hydroraulic** \\ **Conductivity** \\ **(mm/min)** \\ \end{tabular} \\ \hline \multirow{4}{*}{\(0.2\%\)} & CK & & 38.63 \(\pm\) 1.11 c & 10.97 \(\pm\) 1.14 c & 27.66 \(\pm\) 0.33 a & 1.4347 + 0.022 a & 0.69 \(\pm\) 0.01 b \\  & 1 cm & 41.8 \(\pm\) 0.74 b & 16.91 \(\pm\) 0.17 b & 24.89 \(\pm\) 0.6 bc & 1.2987 \(\pm\) 0.003 b & 0.74 \(\pm\) 0.01 a \\  & 2 cm & 42.83 \(\pm\) 0.49 b & 17.43 \(\pm\) 0.11 ab & 25.41 \(\pm\) 0.14 b & 1.2907 \(\pm\) 0.004 b & 0.75 \(\pm\) 0.02 a \\  & 3 cm & 44.57 \(\pm\) 0.49 ab & 17.75 \(\pm\) 0.12 ab & 26.82 \(\pm\) 0.42 ab & 1.2773 \(\pm\) 0.010 b & 0.76 \(\pm\) 0.01 a \\  & 4 cm & 44.07 \(\pm\) 0.28 ab & 18.03 \(\pm\) 0.34 ab & 26.04 \(\pm\) 0.54 b & 1.1637 \(\pm\) 0.033 c & 0.76 \(\pm\) 0.01 a \\  & 5 cm & 42.63 \(\pm\) 0.2 b & 17.23 \(\pm\) 0.04 ab & 25.41 \(\pm\) 0.23 b & 1.2873 \(\pm\) 0.004 b & 0.77 \(\pm\) 0.02 a \\  & 1 cm & 42.83 \(\pm\) 0.49 b & 17.43 \(\pm\) 0.14 b & 25.41 \(\pm\) 0.14 b & 1.2907 \(\pm\) 0.004 b & 0.75 \(\pm\) 0.02 a \\  & 2 cm & 44.1 \(\pm\) 0.12 ab & 17.66 \(\pm\) 0.09 ab & 26.44 \(\pm\) 0.19 ab & 1.2803 \(\pm\) 0.005 b & 0.75 \(\pm\) 0.01 a \\
0.4\% & 3 cm & 44.87 \(\pm\) 0.22 a & 18.1 \(\pm\) 0.08 ab & 26.77 \(\pm\) 0.22 ab & 1.2423 \(\pm\) 0.009 b & 0.75 \(\pm\) 0.02 a \\  & 4 cm & 44.77 \(\pm\) 0.37 ab & 18.43 \(\pm\) 0.28 a & 26.34 \(\pm\) 0.13 a & 1.1483 \(\pm\) 0.067 c & 0.76 \(\pm\) 0.01 a \\  & 5 cm & 42.7 \(\pm\) 0.32 b & 17.23 \(\pm\) 0.03 ab & 25.47 \(\pm\) 0.29 b & 1.2853 \(\pm\) 0.004 b & 0.77 \(\pm\) 0.02 a \\  & 1 cm & 44.57 \(\pm\) 0.3 ab & 17.65 \(\pm\) 0.07 ab & 26.92 \(\pm\) 0.24 ab & 1.2883 \(\pm\) 0.005 b & 0.75 \(\pm\) 0.01 a \\  & 2 cm & 44.07 \(\pm\) 0.3 ab & 17.93 \(\pm\) 0.11 ab & 26.14 \(\pm\) 0.24 b & 1.2693 \(\pm\) 0.002 b & 0.76 \(\pm\) 0.01 a \\
0.6\% & 3 cm & 44.23 \(\pm\) 0.28 ab & 18.33 \(\pm\) 0.34 ab & 25.9 \(\pm\) 0.27 b & 1.274 \(\pm\) 0.003 b & 0.76 \(\pm\) 0.02 a \\  & 4 cm & 44.04 \(\pm\) 0.44 ab & 17.85 \(\pm\) 0.11 ab & 26.15 \(\pm\) 0.34 b & 1.1010 \(\pm\) 0.026 c & 0.77 \(\pm\) 0.01 a \\  & 5 cm & 41.4 \(\pm\) 0.31 b & 17.15 \(\pm\) 0.07 ab & 24.25 \(\pm\) 0.24 c & 1.3040 \(\pm\) 0.007 b & 0.78 \(\pm\) 0.02 a \\ \hline \hline \end{tabular}
\begin{tabular}{c} Different lowercase letters (a-c) within a column indicate significant differences at \(p<0.05\).  
\end{table} 
Table 4: Physical properties of Soil-type A.