祁连山三种主要乔木林细根生物量比较

采用根钻法采集细根，分析了祁连山中段寺大隆林区3种主要乔木植被青海云杉纯林、杨树纯林和祁连圆柏纯林的细根生物量、土壤含水量、土壤容重和土壤养分状况，并在3种森林群落之间进行了比较研究，旨在为该区提高森林生产力和根系碳汇的后续研究提供理论依据。结果表明:研究区内3种乔木植被总细根生物量和活细根生物量之间呈极显著正相关，而细根生物量和土壤水分与土壤容重均呈显著负相关，土壤养分和土壤含水量对细根生物量有着积极的促进作用。3种植被类型的细根生物量都集中分布在20—40 cm土层，而且杨树林分依次是青海云杉林分的154倍、祁连圆柏纯林的308倍；3种植被类型的土壤容重依次为S_d杨 > S_d柏 > S_d杉，且两两之间差异显著；0—10 cm土壤含水量差异显著，青海云杉纯林远高于其他两种乔木植被；另外，3种植被类型土壤中含有的碳、氮含量差异也比较显著。

Comparison of Fine Root Biomass of Three Main Arbors in Qilian Mountains

Using the method of soil core sampling, we analyzed the fine root biomass, soil moisture content, soil bulk density and soil nutrient in 0—40 cm soil layers of the three kinds of main arbor vegetation (Picea crassifolia, Poplar and Sabina przewalskii) in the middle west of the Qilian Mountain, and compared the characteristics of the three vegetation types. The results showed that there was a significant positive correlation between total fine root biomass and live fine root biomass of the three arbor vegetations in the study area, while the soil moisture and soil bulk density were also significantly negatively correlated with fine root biomass. Both soil nutrients and soil water all played the positive role in the development of the fine root biomass. The root biomass of three fine vegetation types mainly distributed in the 20—40 cm soil layers, the fine root biomass of poplar was 154 times of the Picea crassifolia, 308 times of Sabina przewalskii. The soil bulk densities of three vegetation types were significantly different with the rank of S_{d Yang} > S_{d Bai} > S_{d Shan}. Soil moisture appeared significantly different in 0—10 cm layers, it was much higher in Picea crassifolia forest than those under the other two types of vegetation. In addition, the soil carbon content and nitrogen content of three vegetation types were also significantly different.