Over a long period of field experiment

soil water conditions were monitored in different woodlands with plants ofTamarix ramosissima

Populus euphratica

Alhagi sparsifoliaandCalligonum caput-medusae.Soil water retention curves from 0cm to 100cm were fitted for farmland and desert soils based on field data.The results show that

soil water contents gradually increased with depth in 0-250cm.During the growing season of September and October

soil water contents in 0-60cm layer were significantly higher than in the other months.Single heavy rainfall supplied a considerable amount of water to the soil layer of 0-60cm

while deeper soils were affected very little.The monthly change of soil water storage capacity was insignificant

fluctuating between120mm and140mm.However

the storage capacity differed in the fourspecies as in order ofP.euphratica>T.ramosissima>C.caput-medusae=A.sparsifolia.The evapotranspiriation ofP.euphratica

C.caput-medusae

T.ramosissimaandA.sparsifoliaduring the growing season ranged from high to low

respectively

as the highest values were observed in June.Exponential relationship between soil water contents and soil water potentials was found in the layer of 0-100cm for each soil

and all the correlation coefficients were over 0.90.The results provide necessary theoretical references for ecological water needs of vegetation recovery in this area.