延安研究区植被分步恢复的试验研究

Reasearch on Stepwise Restoration of Vegetation in Yan'an Reasearch Area

采用时间和空间序列相结合的方法．对延安研究区的植物群落动态变化及其演替规律观测研究的基础上,完善了前人对此区植物群落演替序列;遵循植物群落演替规律开展植被分步恢复试验，结果表明：在不破坏现有植被的条件下，分步恢复可使当年甘肃鼢鼠危害率减少30％～40％，油松造林保存率提高50％左右，方差分析显示油松和侧柏苗木的高生长和分枝数明显优于一步到位法在退耕地建造的针叶苗木；且在75％覆盖率的灌丛中，油松苗单株抽条长度和单株抽条个数分别是退耕地油松苗木的2．31和2．24倍，生长状况最好。

Combined together with the time and the space sequence, the dynamic varietys and the succession of plant community in gullied rolling loess region were researched. The experiment showed that under the condition of not breaking existing plant,an afforested method hy several steps in uncultivated fields was put forward in gullied roiling loess region of Yan＇an. This method can reduce the damage of Gansu myospalax and increase the afforested sueeess ratio.