松嫩平原两个生态型羊草种群生长机制

对松嫩平原两个生态型羊草种群生长机制进行了研究.结果表明,两个生态型羊草种群分株重与密度之间关系呈幂函数变化，方程中b值（-0.098～-0.272）大于-1.两个生态型羊草种群生物量、分株重随着密度、高度的增加而逐渐增加，它们之间的关系符合幂函数或直线变化规律，达到显著或极显著相关水平.两个生态型羊草种群生物量和分株重随密度和高度的变化速率在营养生长期内均最小.灰绿生态型的变化速率b（0.7872、0.0134）在营养生长期小于黄绿生态型（0.8793、0.0222）；到果后营养期，灰绿生态型（0.8048、0.0303）逐渐超过黄绿生态型（0.7796、0.0258）.两个生态型羊草种群在研究样地环境中未达到环境容纳量，两个生态型羊草种群在整个生育期内不断生长，具有相同的生长规律，且灰绿生态型羊草种群具有更强的生长潜力.

Growth mechanisms of two ecotype Leymus chinensis populations in Songnen Plain

The study showed that there was a power function relationship between weight per tiller and density of two ecotype Leymus chinensis populations in Songnen Plain, and the b value in the function (-0.098 approximately -0.272) was bigger than -1. The biomass and weight per tiller of the two populations increased with their increasing density and height, and the relationships between biomass and density, and between weight per tiller and height were significantly accorded with power or liner function. In the period of vegetation growth, the biomass and weight per tiller of the two populations had the smallest change speed, and the b value of grey-green ecotype (0.7872 and 0.0134) was smaller than that of yellow-green ecotype (0.8793 and 0.0222). On the contrary, in the period of post-fruiting vegetation growth, the b value of grey-green ecotype (0.8048 and 0.0303) became bigger than that of yellow-green ecotype (0.7796 and 0.0258). It was suggested that the two ecotype L. chinensis populations did not reach environment capacity in the sampling field. They kept on growing during the whole growth period, with the same growth pattern, and grey-green ecotype had a stronger potential capability of growing.