Abstract:

Studying soil infiltration capacity and its influencing factors in urban green spaces of Shenzhen can provide references for the construction of sponge city and soil-water conservation in urban green spaces. Aiming at different vegetation types (woody, shrub, lawn) and different soil layers (0-30 cm, 30-60 cm) in urban green spaces, we analyzed the impacts of soil physicochemical properties on soil moisture, by determining the soil saturated hydraulic conductivity (K_fs) with a Guelph infiltrometer. The results showed that: the soil infiltration capacity of Shenzhen green space was poor, the grades of poor K_fs and below were up to 63.42%; the K_fs of the upper soil in woody and shrub was relatively high, which was significantly higher than that of the K_fs of the subsoil (P<0.05); both bulk density and sand particle contents of green spaces were quite high with 1.62 g/cm ³ and 52%, respectively; the soil texture had a significant effect on K_fs, and there was a positive correlation between sand particle contents and K_fs (P<0.01); soil bulk density, initial moisture content and gravel content showed a significantly negative correlation with K_fs (P<0.05). In conclusion, the soil infiltration capacity in urban green spaces of Shenzhen is very poor, and reducing the compaction degree and increasing sand content could improve soil infiltration.

Key words: urban green spaces, soil infiltration, soil physical characteristics, Shenzhen