不同类型土壤中酸枣的生物量构成与碳氮特征

在河南省暖温性灌草丛类草地中,酸枣(Ziziphus jujuba)+草本是最典型的植被型之一。以酸枣为研究对象,探讨3种土壤类型对酸枣生物量构成和碳氮含量特征的影响。结果表明,棕壤土的全碳含量、全氮含量及碳氮比与黄绵土和褐土间存在显著差异(P0.05),其更有利于酸枣的物质积累,尤其是老枝生物量达到显著水平(P0.05)。酸枣叶片的固碳能力最低,新枝最高。此外,酸枣叶片的固氮能力最强,是其它组织的2~3倍。其中棕壤土酸枣叶片的全碳含量与全氮含量显著高于黄绵土和褐土的(P0.05),而新枝间差异不显著(P0.05)。因此,就物质积累、碳氮固定而言,棕壤土有利于酸枣的生长发育,促进其发挥相应的生态功能。

Analysis of biomass compositions and C,N characteristics of wild jujube in different soil types

In the warm-temperate shrub grassland of Henan Province,wild jujube(Ziziphus jujuba)is one of the most typical vegetation types in the herbaceous plant community.In this study,wild jujube was selected as the research object to discuss the effects of three soil types on the biomass composition and carbon/nitrogen content of the subjects.The results indicated that the total carbon content,total nitrogen content and C/N ratio of brown soil were significantly different from loess soil and cinnamon soil(P<0.05),which was more favourable forbiomass accumulation,especially for the older branches of wild jujube(P<0.05).The leaves of wild jujube had the lowest carbon sequestration ability,but the new branchesshowed the highest ability.In addition,the nitrogen fixation ability of the leaves was the highest when compared with other tissues,which was 2 to 3 times higher than that of new branches,old branches or roots in different depths.The total carbon and total nitrogen content of wild jujube''s leaves in brown soil were significantly higher than those of loess soil and cinnamon soil(P<0.05),but there was no significant difference in the new branches among all soil types(P>0.05).Therefore,in terms of biomass accumulation and carbon and nitrogen fixation,brown soil is beneficial for the growth of wild jujube,and can help wild jujube perform its corresponding ecological functions.