Spatial pattern of Bromus inermis (poaceae) in Otindag Sandland, China

Bromus inermis Leyss. is a dominant perennial grass in Othidag Sandland. Spatial patterns of B. inermis plants, soil water content, soil salinity and their interaction were analyzed at different scales. At a large scale, B. inermis cover, soil water content and soil salinity were monitored along two 5 m×3 km transects. Transect I was perpendicular to II, and each transect had 600 plots. For a transect, spatial patterns were similar among B. inermis cover, soil water content and soil salinity. However, these patterns differed between the two transects. Bromus inermis cover, soil water content and soil salinity were significantly positively correlated (P < 0.05). At a small scale, similar things were monitored in the B. inermis community, using a 4m×4m sampling site, which consisted of 400 plots, each 20 cm×20 cm. Spatial patterns among aboveground biomass, number of ramets and soil salinity were similar, but they differed from the spatial pattern of soil water content. There were significant positive correlations between number of ramets and aboveground biomass of B. inermis (P < 0.01) and between soil water content and soil salinity (P<0.05). Moreover, number of ramets and aboveground biomass of B. inermis were significantly positively correlated with soil water content (P<0.05), but not with soil salinity. These results demonstrate a spatial relationship between vegetation characteristics and soil properties.