红三叶、鸭茅生物量和叶面积时空结构特征

研究红三叶、鸭茅各生育期生物量和叶面积时空结构。结果表明:鸭茅下半部生物量较大,红三叶各层分布较均匀,其上半部所占比例明显大于鸭茅;随着生育期的后移,生物量的差异愈加明显,鸭茅呈现下繁草特性,红三叶则呈现上繁草特性;鸭茅地下与地上生物量的比值显著高于红三叶,随着生长期的后移,红三叶根量的变化不大,而鸭茅增加较明显;留茬高度<8cm,对鸭茅收获量的影响比红三叶大,而>8cm则相反;除苗期外鸭茅叶量的比例高于红三叶;在现蕾期或孕穗期以后,两种牧草的叶量下降极为明显;在现蕾期或孕穗期前刈割,可获得最大的光合生产效率。

Red Clover and Cocksfoot Biomass and the Spatio-Temporal Structure of Their Leaf Area

A study on the biomass and the spatial structure of leaf area of red clover and cocksfoot reveals that the cocksfoot boasts lusher close-to-ground biomass,while the red clover's aboveground biomass develops eventy. The red clover's upper part aboveground biomass proportions larger of the total biomass than that of cocksfoot of its total.Following the developing growth stage,the difference of the amount of biomass of the two herbages becomes more noticeable.The cocksfoot plants grows in a triangular shape,while the red clover plant looks like a reversed triangle.The ratio of the underground and aboveground biomass of cocksfoot is markedly higher than that of red clover, whose root biomass remains the same as the plant grows,whereas the cocksfoot underground biomass develops vigorously.Stubble height of less than 8 cm affects the growth and yield of cocksfoot but not to red clover,while a stubble height of more than 8 cm reverses the effect to the two herbages.The amount of biomass of cocksfoot rises higher than that of red clover except during the seedling stage.Both herbages decrease their biomass amount after flower budding or spiking stage.Harvesting the herbages before these periods ensures their maximum photosymthetic productive efficiency.