基于一维土柱试验的宁南山区杏树林土壤水分运移过程模拟OA

[Objective]To clarify the characteristics of soil water infiltration,capillary water transport,and changes in hydraulic parameters in apricot(Prunus armeniaca L.)orchards in the southern mountainous region of Ningxia.[Method]Based on the soils from farmland(CK)and apricot orchard aged 3,10,17,23,and 35-year-old,ring corers were employed to obtain 0-40 cm surface soil samples for bulk density de-termination.Based on bulk density,CK and soils of different forest ages were reconstructed.One-dimen-sional vertical soil column experiments were conducted to analyze variations in wetness peak,cumulative infiltration volume,infiltration rate,and capillary water movement characteristics across different forest ages.Four infiltration models were applied to simulate the water infiltration process and evaluate their ap-plicability.In addition,soil hydraulic parameters were inversely estimated using Hydrus-1D,and dynamic simulation of soil profile moisture distribution was conducted.[Result]After 280 min of infiltration,com-pared with CK,the wetting front depth,cumulative infiltration volume,and steady-state infiltration rate all showed a decreasing trend in the 3-,10-,17-,23-,and 35-year-old orchard soils.Horton model performed the best,followed by General empirical model,Kostiakov model,and Philip model.Among the In Hydrus-1D-inverted hydraulic parameters,the inverse of the air suction coefficient α gradually increasesed with orchard age,while the residual water content θr,saturated water content θs,shape factor n,and saturated hydraulic conductivity Ks gradually decreased.Hydrus-1D simulations of soil profile moisture content showed R2 values ranging from 0.91 to 0.96,with RMSE and MAE both≤2%.Capillary rise height and water uptake gradually decreased.[Conclusion]With increasing orchard age,both soil water infiltration ca-pacity and capillary transport efficiency significantly declined,revealing that long-term cultivation of artifi-cial apricot trees exacerbates excessive depletion of deep soil moisture in the southern Ning Mountains.These findings contribute to enhancing productivity in artificial forest lands within the southern Ning Moun-tains and offer valuable guidance for the establishment and sustainable development of artificial forests in arid and semi-arid regions.