Vegetative reproduction characteristics of Leymus chinensis populations in Tumuji National Nature Reserve,Inner Mongolia

Quantitative features of vegetative reproduction of grey-green and yellow-green Leymus chinensis on meadow and meadow steppe were studied in Tumuji National Nature Reserve,Inner Mongolia.In two vegetation types,the number and biomass of two ecotype L.chinensis tillers consisted of four age classes of which the 4-year tillers were the fewest.The tillers were stable or expansive age structures.The 2-year rhizomes were dominant,and were stable age structures.The productivity per tiller of 1-year tillers of the two ecotypes was the highest and the productivity gradually decreased with increasing age classes.The productivity per tiller on meadow steppe was significantly higher than those of meadow grey-green and yellow-green ecotypes.The 1-year or 2-year rhizome productivity of the two ecotypes was the highest.In temperate herbaceous communities,increased or stable age structures,vigorous matter production and storage of both young tillers and rhizomes were essential reasons for sustaining flourishing perennial clonal plants.