割草干扰对典型草原土壤种子库种子数量与组成的影响 Ⅳ群落生物量的组成与种子数量组成的比较

The Influence of Mowing on Seed Amount and Composition in Soil Seed Bank of Typical Steppe Ⅳ The Comparing of the Compositions of Community Biomass and Seed Amount

对典型草原群落生物量的组成与种子数量的组成进行了比较研究 ,主要结果如下 :在割草干扰下 ,割一年休一年和一年割一次的群落生物量分别较对照下降了 1 5 .5 8%和 2 5 .31 % ;具有生命力的种子数量分别较对照下降了 1 1 .35 %和 2 7.33% .种群相对生物量与相对种子数量没有一致的关系 ,表现为 5种形式 ,即生物量较高而种子数量较低 ;生物量较低而种子数量较高 ;生物量与种子数量相近 ;有生物量而无种子数量和无生物量而有种子数量 .不同科植物生物量与种子数量有一定的差异 .禾本科植物生物量较高 ,而种子数量较低 ;菊科植物生物量较低 ,而种子数量较高 ,豆科植物生物量一般高于种子数量 ;其余科植物均有各自的特点 .不同生活型植物生物量与种子数量也有差异 .多年生草本植物生物量最高 ,而种子数量较低 ;一年生、二年生和一、二年生草本植物生物量较低 ,而种子数量占总量的一半以上 ;

A comparative study on the compositions of community biomass and seed amount was discussed.The major results are as follows:under mowing disturbance,the community biomass in the treatment of mowing a year and stopped next year and mowing once a year decreased by 15.58% and 25.31% respectively than that in the contrast treatment.The seed amount with vitality decreased by 11.35% and 27.33% respectively than that in the contrast treatment.The plant population relative biomass had no unanimous relation with relative seed amount.There were 5 forms:the biomass was higher while the seed amount was lower;the biomass was lower while the seed amount was higher;the biomass was similar with seed amount but no biomass.There were certain differences between biomass and seed amount of different families.The biomass of Gramineae plant was higher while its seed amount was lower;Leguminosae plant biomass was usually higher than its seed amount;the plant of other families have their respective characteristics.There were differences between biomass and seed amount of different life form plant.The biomass of perennial herb was the highest but the seed amount was lower;the biomass of annual herb,biennial herb and annual biennial herb were all lower,but their seed amounts were above half of total;either biomass or seed amount of shrub and shrublet were lower.