樟子松林下土壤有机碳和全氮储量研究

本文通过调查分析我国最重要樟子松原产地—红花尔基的樟子松林下土壤有机碳(SOC)和全氮(TN)及其机械组成，发现樟子松林下的土壤有机C和N含量与其机械组成呈显著相关，与粉粒含量相关系数高达0．7028和0．7209，与土壤容重呈现负相关，相关系数达0．5760和0．5937。樟子松林土壤平均C、N密度分别为19．5kg／m^2和1．8kg／m^2，比同地区的桦木林和农田土壤低。同时也发现，樟子松林土壤C、N含量与地形有关，一般阳坡高于阴坡，下坡高于上坡；天然樟子松林的土壤C、N密度随年龄先出现增长，到25年时达到最高值，30年以后有下降趋势，这与土壤质地的变化密切相关。在该地区，不同植物群落类型的土壤C、N含量的差异也主要受土壤质地变化的影响。

CARBON AND NITROGEN POOL IN FOREST SOIL UNDER PINUS SYLVESTRIS VAR.MONGOLICA

Based on field investigations of Honghuaerji, the native habitat of Pinus sylvestris var. mongolica, it was found that in the forest soil organic Carbon, and total Nitrogen were significantly correlated with and soil texture., especially with silt content, showing a correlation coefficient being as high as 0.7028 and 0.7209, respectively, but negatively with bulk density, being 0.5760 and 0.5937, respectively in correlation coefficient. In comparison with the forestland under white birch and farmland, the forestland under Pinus sylvestris var. mongolica was relatively lower in content of SOC and TN, being 19.5kg/m2 and 1.8kg/m2 respectively. At the same time, SOC and TN in the forestland under Pinus sylvestris var. mongolica were also found related to topography. Generally, they were higher in the soil on the sunny slope than in the shady slope and in the down slope than in the upper slope. Besides, they were increasing with age of the forest and rising to the peak when the forest was 25 years old, and then showed a decreasing trend after it was 30 years old, which was closely related to change in soil texture. So was the difference in SOC and TN contents between soils under different plant communities.