人工针叶林林冠空隙土壤的研究

作者研究了北京西山地区人工针叶林林冠空隙和林冠下的土壤及植被状况.结果表明:①林隙中乔木物种丰富度指数与林下一致,但灌木和草本的物种丰富度指数比林下高.②林隙土壤的枯枝落叶层比林下薄,其组分主要是草本和根系盘结物且呈半分解状态;林隙土壤的剖面形态特征,除A层的颜色、根系含量有别外,与林下土壤无明显区别.③油松林林隙土壤中A层的土壤有机质、全氮、有效磷和速效钾分别比林冠下土壤高10.7%,345%,25 .8%和35.7%.④油松侧柏混交林中林隙土壤A层的土壤有机质、全氮、有效磷和速效钾分别比林冠下土壤高4.7%,12.5%,9.4%和31.1%.⑤林隙土壤的pH、过氧化氢酶和多酚氧化酶没有明显的变化规律.⑥建议对林隙土壤水分的时空动态变化进行研究.

Soils in forest gaps in artificial coniferous forests

The authors had studied the soils and vegetation in forest gaps and under the canopy in the artificial coniferous forests of the West Mountain of Beijing. The results showed that:①The richness indexes of tree layer in forest gaps were similar to these under the canopy, but the richness indexes of shrub and herb layer were higher than those under the canopy. ②The litter layer in forest gaps was thinner than that under the canopy, the composition of the litter layer was herb remains and root twister while that was in half decomposition; The morphological characteristics of soil profile except the color and the root content in humus layer in forest gaps were not apparently different from those under the canopy.③ The content of the soil organic matter, total nitrogen, available phosphorus and potassium of the humus horizon in forest gaps were 10 7%, 34 5%, 25 8% and 35 7% more than those under the canopy in Pinus tabulaeformis forest. ④Those items in forest gaps were 4 7%, 12 5%,9 4% and 31 1% more than those under the canopy in Pinus tabulaeformis and Platycladus orientalis mixed forest. ⑤The changes of soil pH, the oxido reductase activities had no significant trends. ⑥The authors proposed that soil water trends of time and space in forest gaps should be studied.