Variations in Soil C, N, P Stocks and Stoichiometry With Soil Depth and Forest Types in Qilian Mountains of Northwest China

Forests ecosystem plays a significant role in supplying multiple services given the unique properties of forest soils, which elements C, N, and P are essential to support soil fertility site productivity. However, at different depths between plantation forests (PF) natural (NF) have not been well quantified. Therefore, current study was carried out Qilian Mountains northwest China determine difference PF NF properties, both physical (e.g., bulk density, BD) chemical pH value, contents, stocks, stoichiometry organic carbon (SOC), total N (TN), (TP)). Research analyzed samples (0–20, 20–40, 40–60, 60–80, 80–100 cm). The results showed that soils’ values BD were significantly higher ( p ? 0.05) than increased with depth. contents SOC, TN, TP decreased considerably depth then stabilized cm. PF, confirming quality had fully recovered yet. stocks SOC TN quickly up 40–60 cm gradually. Additionally, C:P N:P rising depth, while C:N ratio remained unchanged. ratios lower NF, NF. In conclusion, show soils present but (or nearly equal) (under same age group tree species composition). These imply maintaining avoiding their replacement by can help keep related services.