Riparian soil is influenced by freshwater and terrestrial environmental factors and the ecological process, showing transparent spatial pattern in physical and chemical features. How does the soil feature change along the lateral and longitudinal direction along the river channel? Liaohe River Reserve, which was established in 2010 and has experienced 6 years of natural recovery, was selected to reveal the spatial longitudinal and lateral heterogeneity pattern and the respective driving factors.
Three river segments from upper to the lower part of the river ware selected, and in each segment 4 transects were set laterally beginning from the wet river channel edges. In each transect soil samples were surveyed. Redundancy analysis (RDA) was run to analyze the relations between soil properties and environmental factors.
Results/Conclusions
Results showed that generally, the soil had high contents of sand and was poor in nutrients. Apart from available phosphorus, other soil properties had no significant difference along longitudinal gradients. Clay and silt contents increased along the buffer distance gradients from river edge to upland, while sand decreased. Soil nutrient contents showed a trend of increase along the lateral gradients. Altitude, buffer distance from river edge, distance from the nearest farmland and sand contents were indicated as the statistically significant factors affected soil properties heterogeneity. Sandy soil is more susceptible to flood and water fluctuation in Liaohe River Reserve, which results in the soil erosion.
Revegetation and soil reinforcement was crucial for the restoration of degraded riparian systems. Soil quality wasn’t improved greatly at the early restoration stage in Liaohe River Reserve, and chronosequence studies should be conducted to understand the dynamics of riparian restoration further.