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Caragana microphylla is the dominant perennial shrubs and widely used to stabilize shifting sand dunes in semi-arid, north China. To confirm the influence of plantations on soil water condition, we determined the soil moisture and evapotranspiration under different densities of sand-fixing C. microphylla shrubs during growth period. Result showed that the soil moisture under shrubs continued decreasing with the increasing of plantations densities. Soil moisture under 0.5 mxlm and lmx 2m densities of C. microphylla shrubs are under wilting humidity (1.55%) level, however, soil moisture under 2 m x 2 m densities and savageness C. microphylla shrubs always keep above 1.6% during growth season. Evapotranspiration of all shrubs are low than rainfall and occupied above 90.3-98.5% of rainfall during growth phases, and continually increased with the increasing plant densities. The 0.5 mxlm density shrubs have the highest evapotranspiration, about to 298.3 mm (2009)/235.7 mm (2008) and occupied above 98.5% (2009)194.4% (2008) of rainfall at the same time. The 2 m x 2 m density shrubs have the lowest evapotranspiration, about 283.4 mm (2009)/230.7 mm (2008), and soil moisture surplus 20.8 mm (2009)/19.0 mm (2008) at the end of growth season. According to soil moisture and evapotranspiration, the 2 m x 2 m of C. microphylla shrubs is applicable density in Horqin sandy land, north-east of China. (C) 2013 Elsevier B.V. All rights reserved.