摘要
祁连山植被的水源涵养作用对于维持黑河的流量至关重要，地下微生物参与生态系统的物质和能量循环，维持了地上植被的稳定，因而具有重要的生态作用．研究分析了祁连山冰沟流域不同海拔梯度上硝化细菌、反硝化细菌、固氮细菌、解磷细菌和植酸矿化细菌的数量随土壤深度的变化规律．结果表明：随土壤深度的增加，氮磷循环细菌的数量下降；随海拔升高，硝化细菌相对减少，而反硝化细菌和固氮细菌呈增多的趋势．典范对应分析（CCA）显示，硝化细菌的数量变化主要受地下生物量和土壤pH值的影响，而反硝化细菌、固氮细菌、解磷细菌和植酸矿化细菌主要受植被盖度、地上生物量和土壤含水量的影响．聚类分析表明，低海拔（E1-2905m和E2-3128m）浅层土壤（0～40cm）聚类，而其深层土壤（60cm）与高海拔（E3-4130m）土壤聚类，说明高海拔处土壤发育与低海拔处深层土壤的早期发育相类似．研究表明，高山地区氮磷循环细菌数量的变化受到海拔主导下植被和土壤理化因子的共同作用．
The Binggou is located in the upper reaches of the Heihe River, Southern Qilian Mountains. Vegeta- tion plays an important role in sustaining a stable runoff of the Heihe River in this region. There are many resear- ches about hydrology and vegetation in the region, but less about underground microorganisms. In this study, the functional microorganisms participated in N and P cycles are focused on. A few vegetation quadrats were investi- gated in situ and soil samples were taken at three altitudes. The soil physicochemical properties were determined and the functional microorganisms including nitrifier, denitrifier, diazotroph, phosphate-solubilizing bacteria （PSB） and phytate-mineralizing bacteria （PMB） were cultured in laboratory. Colony forming units （cfu） of these functional microorganisms were counted. It is found that number of the functional microorganisms decreases with soil depth. Interestingly, number of nitrifier decreases and that of denitrifier and diazotroph increases with altitudes （2 905 m - 4 130 m a. s. 1. ）. Canonical correspondence analysis （CCA） shows that number of nitrifi- er is mainly affected by the underground biomass and the soil pH value, while number of denitrifier, diazotroph, PSB and PMB correlates with soil moisture, vegetation coverage and aboveground biomass. Hierarchical cluster analysis indicates that the superficial soil layers （0 -40 cm） at lower altitudes （El-2 905 m and E2-3 128 m） will cluster together. The deeper soils （60 cm） at lower altitude cluster with the soils at higher altitude （E3- 4 130 m）. This study demonstrates that number of the functional microorganisms mainly depends on altitude and its covariables in alpine soils.
出处
《冰川冻土》
CSCD
北大核心
2014年第1期214-221,共8页
Journal of Glaciology and Geocryology
基金
国家自然科学基金项目(91025002
31070357
31100365)
中国科学院重点部署项目(KZZD-EW-04-05)资助
关键词
氮磷循环细菌
祁连山
海拔
土壤理化因子
植被
N- and P-cycling bacteria
Qilian Mountains
altitude
soil physicochemical factors
vegetation
