黄土高原子午岭不同林龄天然油松林土壤微生物组成研究  

Composition Study of Soil Microorganism in Natural Chinese Pine Forest with Different Growth Years in Ziwuling Forest Region of the Loess Plateau

作　　者：王金成[1] 李海燕[1] 梁健[1] 

机构地区：[1]陕西师范大学生命科学学院,陕西西安710062

出　　处：《水土保持通报》2010年第1期43-48,138,共7页Bulletin of Soil and Water Conservation

基　　金：国家重点基础研究发展(973)计划项目(2002CB111505)

摘　　要：为了认识土壤微生物在天然油松林发展过程中的地位和作用,利用"平板培养法"和"MPN法"测定了不同林龄天然油松林土壤微生物3大类群和主要功能群组成;用"氯仿熏蒸法"测定了土壤微生物生物量碳(MBC)。结果显示,由10a林发展到25a林,土壤微生物总数量和细菌数量呈上升趋势,25a之后逐渐下降;细菌数量在土壤微生物中占绝对优势,真菌及放线菌数量较少;10a林氨化细菌及纤维素分解菌数量最高,之后整体呈下降趋势;由10a林发展到25a林,固氮菌数量上升,25a后呈下降趋势,到40a后趋于稳定;由10a至40a林,硝化细菌数量无显著变化,但由40a至70a林,其数量显著增加;土壤微生物综合性指标Shannon—Wiener指数,由10a林发展到70a林,呈增加趋势;土壤MBC以10a林最低,之后呈增加趋势。研究结果表明,天然油松林土壤微生物组成有其独特的规律及变化原因。本研究从土壤微生物学角度为黄土高原油松林的保护和管理提供了借鉴。The natural chinese pine forest is an important vegetation type in vegetation protection and restoration of the Loess Plateau. To further understand its status and functions during its development process, the three main micro-groups and the main functional groups of soils were investigated using the method of plate cultivation and MPN method. Besides, the soil microbial biomass carbon （MBC） was determined by the method of chloroform fumigation. Results showed that there was an increasing trend for the amounts of microorganisms and bacteria in the forest with the growth years from 10 to 25 and after that, they begun to reduce. Meanwhile, the amount of bacteria hold an absolute predominance over the total microorganism amount and the rest two types of microorganisms, fungi and actinomycetes, were fewer. The amounts of am- monifying bacteria and cellulose-decomposing microorganisms appeared in the forest with the growth years of 10 and after that they showed a decreased trend. The azotobacter amount showed an increasing trend in the forest with the growth years from 10 to 25, then decreased until 40 years forest, and after that showed a sta- ble trend. There was no significant variation in nitrifying bacteria for the forest with the growth years from 10 to 40, but its amount significantly increased after that. Meanwhile, the comprehensive indexes of soil microorganism （Shannon Wiener） and the MBC showed an increasing trend from 10 to 70 years. All above results demonstrate that there are a unique principle and the reasons of variation in soil microorganism composition in the natural chinese pine forest. This study may offer a guidance and reference significance to the protection and management of the natural chinese pine forest on the loess plateau based on soil microbiology.

关 键 词：黄土高原 林龄 天然油松林 土壤微生物 

分 类 号：Q938.13[生物学—微生物学]