Ecological characteristics ofAgriophyllum squarrosum,a pioneer annual on sand dunes in eastern Inner Mongolia,China

A field survey was conducted in a semi-arid region of Inner Mongolia, China, to clarify the ecological characteristics ofAgriophyllum squarrosum (Chenopodiacea), which is an ephemeral in shifting sand dunes. The habitat ofA. squarrosum is extremely unstable, that is, the surface substrate frequently shifts, the soil water-content is highly variable and the site does not permit the growth of any other plant species.Agriophyllum squarrosum is able to invade as a pioneer because of the elongation of its fine roots, which are well adapted to dry sandy soil and able to penetrate deep soil layers containing moisture. The biomass and the pod numbers increased under conditions where enough water was supplied. However the biomass at sites where the wind was strong was relatively small.