摘要
1.禾草与非禾草植物粗蛋白质含磷量季节动态有共同趋势。在生长期5-10月有两个高峰值。即双峰型,第一次是返青后,另一次是雨季后。其含量的动态特征与其生长发育节律有关。由于降水影响其生长发育节律,故含量动态与气候条件有关。植物中粗蛋白质含量与含磷量成直线回归关系。2.禾草与非禾草植物灰分含量动态有不同特点。禾草植物灰分合量为“浓缩型”,后期较高,但其变幅不像氮、磷那么大。而非禾草植物动态不甚明显。3.目前这种季节打草所贮干草其含磷量缺乏是显而易见的。
The seasonal variations in the N, P, K, Fe and ash contents of 9range plants were studied by half-monthly samplings from the same sitein the Stipa grandis steppe at the Inner Mongolia Grassland EcosystemResearch Station (GERS)from May to October, 1981. Trends in crude pr-otein(CP)and P were similar in grass and nongrass plants. Highest conce-ntrations occurred at the ends of May and June, and the lowest in Octo-ber. The seasonal variations were related with the growth rhythm of pl-ant. Because precipitation affects the growth rhythm of plant, so it inf-luences the seasonal variations of nutritional composition. The ash var-iations are different for grass and woody plant. The variations of grassbelong to the concentrated type and its concentration in the later stageis less than in the earlier one; but the variations of woody plant is tnoso marked. There is authentic regression interrelation between the crudeprotein concentration and the phosphorus concertration. The P concentr-ation of harvested grass is lower because its concentration in harvestperiod was low.
关键词
季节动态
营养物质
草原
Seasonal variation
Nutritional composition
Steppe
