Agroforestry Mode Water Characteristics Of The Taihang Mountain

Based on the SPAC water transportation theory, a soil layered waterbalance model for the simulation of the two dimensional soil-water content ina megranate-wheat alleycrop stand was developed in this paper. Testing themodel with the observed data between April and May in 1999,the simulatedresults fit well with the observed data.Soil profile water storage of different distance from tree row, soilevaporation and plant transpiration, soil water uptake by plant, soil waterexchange between different soil layers and water interception by plat aresimulated by using the field observing data from April 1 to 29 May in l999.Using the simulated results, the characteristics of the water consumption ofagroforestry system were discussed. The main results are as follows:(l)There are distinct differences in watr storage of different distancefrom megranate row for 80cm depth soil in the growth stage.(2)80% of fine roots of megranate row and 95% of winter wheat roots areconcentrate in the top 60cm soi1 layer. It means there is lack of spatialcomplementarity between megranate row and winter wheat in water use.(3)About half of soil water absorbed by megranate row comes fromwinter wheat field. It shows megranate row and winter wheat are competitionfor soil water. Though the total water consumption of agroforestry in thegrowth stage of winter wheat are dominated by winier wheat.(4) Megranate row transpiration is the main part of megranate rowevapotranspiration, but megranate row soil evaporation also has aconsiderable proportion. Winter wheat evapotranspiration is dominated bywinter wheat transpiration, winter wheat soil evaporation is very little.Megranate row evapotranspiration and winter wheat evapotranspiration havesequential complementarity.(5)Agroforestry in the hilly area of TaiHang Mountain is reasonable intheory and feasible in practice.