Intra-specific variations of two Leymus chinensis divergence populations in Songnen Plain, Northeast China. E-mail: wangrz@btamail.net.cn

Article type: Research Article

Authors: Wang, Ren-zhong

Affiliations: Laboratory of Quantitative Vegetation Ecology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China

Abstract: Population demography, seed production, biomassallocation, net photosynthesis and transpiration of two Leymuschinensis divergence populations and between two years in Songnenplain, northeast China were compared. Strong differences betweenthe dry 1997 and moist 1998 occurred in vegetative shoot and sexualshoot densities, sexual differentiation and tiller densities, aswell as in the lengths of inflorescence, seed numbers perinflorescence, seed weights and biomass allocation in eachpopulation respectively (P<0.01). While strong differences betweenthe two populations occurred in vegetative shoot densities, sexualshoot densities, sexual differentiation and seed weights in eachyear (P<0.01). The differences between the two populations intiller densities and in biomass allocation to sexual shoots were significant (P<0.05). But there were no significant differences between the two populations in the lengths of inflorescence, seed numbers per inflorescence and biomass allocation to rhizomes and vegetative shoots (P>0.05). Excepting the transpiration rate in the early June, the differences between the two populations in net photosynthesis and transpiration rate of vegetative shoots and sexual shoots were strongly significant in the early June and July respectively (P<0.01). Relative stable variations in population demography and physiological traits between the two populations indicated that they are divergently in the Songnen Plain.

Keywords: population demography, seed productions, biomass allocation, net photosynthetic rate, transpiration rate, Songnen Plain, Leymus chinensis populations

Journal: Journal of Environmental Sciences, vol. 14, no. 1, pp. 20-26, 2002