## 3 Results
### Relationships among Soil Physicochemical Properties, Microbial Biomass and Enzyme Activity  
The relationships between soil physiochemical properties and soil microbial biomass indices (i.e., microbial biomass C, N, P, microbial biomass C:N:P stoichiometry, and microbial quotient) were examined using RDA and Pearson's correlation analysis (Figure 3, Table S2). The results showed that SWC were significantly and positively correlated with all soil microbial biomass indices. STC and SOC showed significant positive correlations with MBC, MBN, MBP, MBC:MBN, MBC:MBP, and MBN:MBP, but no significant correlations with MBC:SOC. Furthermore, BD was negatively correlated with all microbial biomass indices, but only closely related to the changes in MBC, MBC:MBN, and MBC:SOC. In particular, pH and SIC had no significant effect on all soil microbial biomass indices. Altogether, SWC, STC, and SOC had major effects on soil microbial biomass indices, and BD had minor effects on soil microbial biomass indices, while pH, EC, and SIC had no effects on all soil microbial biomass indices. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Metric** & **Sand Soil** & **Mixed Soil** & **F (\(\alpha\), S)** & **\(p\)** \\ \hline BG/(BG + AKP) & 0.302 \(\pm\) 0.001 & 0.262 \(\pm\) 0.005 & 67.09 & \(<\)0.01 ** \\ BG/(BG + NAG) & 0.85 \(\pm\) 0.01 & 0.90 \(\pm\) 0.01 & 116.41 & \(<\)0.01 ** \\ Vector length & 0.90 \(\pm\) 0.01 & 0.94 \(\pm\) 0.01 & 39.91 & \(<\)0.01 ** \\ Vector angle & 70.41 \(\pm\) 0.06 & 73.82 \(\pm\) 0.20 & 278.87 & \(<\)0.01 ** \\ \hline \hline \end{tabular} Values are expressed as mean \(\pm\) SE, \(n=3\). All samples included the values for \(\beta\)-1,4-glucosidase (BG), \(\beta\)-N-acetylglucosamine(NAG), and alkaline phosphatase (AKP). Vector angles in degrees, all other vector characteristics unitless. Calculations for vector length and vector angle described in the main text. ** means that the differences between the two lands for a metric is significant at the 0.01 level.  
\end{table} 
Table 3: The vector characteristics of enzyme activity in sand vs. a mix of sand and feldspathic sandstone. Figure 2: Soil extracellular enzyme activity and ecoenzymatic stoichiometry in sand vs. a mix of sand and feldspathic sandstone. * and ** indicate statistical significance at the 0.05 and 0.01 probability levels, respectively. Error bars are the standard errors (\(n=3\)). In addition, Pearson's correlation coefficients showed a significant correlation between soil extracellular enzymes activities, ecoenzymatic stoichiometry, and vector characteristics of enzyme activity with edaphic abiotic and biotic factors (Table 4). The activities of all individual enzymes had closely relationship to SWC, STC, SOC, porosity, field capacity, MBC, MBN, MBP, MBC:MBN, and MBC:MBP, but had little relationship to the pH, EC, or SIC. In detail, SWC, STC, SOC, porosity, field capacity, MBC, MBN, MBP, MBC:MBN, and MBC:MBP showed a significant positive correlation with all individual enzyme activities. Conversely, CBH had no significant correlation with MBN:MBP and MBC:SOC, and BX was not closely related to MBC:SOC. Additionally, the activities of BG, AKP, and BX were also closely related to BD (negative correlation). For the ecoenzymatic stoichiometry and vector characteristics of enzyme activity, they were all significantly associated with all edaphic biotic factors except MBC:SOC, but only with some edaphic abiotic factors (e.g., BD, SWC, STC, SOC, porosity, and field capacity). Like individual enzymes, pH, EC, and SIC had no significant effect on the ecoenzymatic stoichiometry and vector characteristics of enzyme activity. Interestingly, SWC, STC SOC, porosity, and field capacity showed significant negative correlations with BG:AKP, NAG:AKP, and BG/(BG + AKP), but showed significant positive correlations with other enzyme activity metrics (i.e., individual enzyme activity, ecoenzymatic stoichiometry, and vector characteristics of enzyme activity).