石羊河上游草地植物种群特征与生产力关系研究

Relationships between population characteristics and productivity of grassland plants in the upper Shiyang river

对石羊河上游各类草地群落16种主要植物种群特征与其自身初级生产力之间的关系进行了探讨.结果表明:草地群落16种主要植物密度与初级生产力存在相关性,其中蒿草、针茅等7种达到极显著水平(0.95<r<0.99,P<0.01),苔草、扁穗冰草等7种达到显著水平(0.89<r<0.94,P<0.05),冷蒿、骆驼蓬与生产力的相关性不显著,r分别为0.790 1、0.671 3(P>0.05);草地群落植物盖度与生产力关系的研究中,冷蒿、醉马草等5种植物呈显著性相关(0.84<r<0.95,P<0.05),其余都呈极显著性相关(0.96<r<1,P<0.01),说明植物群落初级生产力随着植物盖度的增加而增大;分析各类草场主要植物种群密度和盖度与生产力之间的相关性,发现盖度与生产力的显著性普遍高于密度与生产力的水平,即盖度与生产力的拟合函数关系更能贴近生产实际,更方便于农牧民判断草地实际生产力,对保护草地、可持续利用草地具有十分重要的意义.

The relationships between population characteristics and its primary productivities of sixteen main grass species of grassland communities in the upper Shiyang river were researched.The results indicated that：（1）A correlation in certain degree was found between density and primary productivity of sixteen main grass species.Among them,the correlation of seven species was significant at 0.01 level（0.95〈r〈0.99,P〈0.01）,other seven species at 0.05 level（0.89〈r〈0.94,P〈0.05）.The correlation of the rest two species（Artemisia frigida and Peganum harmala） was not significant（P〉0.05）;（2） A correlation was also found between coverage and productivity of the sixteen grass species.Five species was significant at 0.05 level（0.84〈r〈0.95,P〈0.05）,the rest at 0.01 level（0.96〈r〈1,P〈0.01）.The correlation meant primary productivity increased along with coverage;（3）The correlation between coverage and productivity was higher than that between density and productivity at large.So that the function relation between coverage and productivity was more practicable in production.This made it more convenient for the herdsman to estimate the real productivity,and had a great meaning for conserving the grassland and utilizing it continually.