古浪县北部荒漠草场改良过程中植被变化动态的研究

The research on the development of the grassland vegetation during the course of the improvement and recovery of the grassland in the northern deserts of Gulang County

结合古浪县北部荒漠草场生态治理工程,在自由放牧、围栏封育和人工补播条件下,对退化草场的植物种类、植被盖度、生产力水平等进行了初步的调查研究。结果表明:1)随自由放牧时间的延长,草场植被盖度、生产力逐渐下降,植物种类逐渐减少;2)随围栏封育时间的延长,放牧压力减轻,草场植被盖度、生产力逐渐提高,物种丰富度增加;3)人工补播种草加快了草场的恢复演替速度。围栏封育和人工补播使草场植物群落优势种得到加强,沙蒿Artemisiadesertorum,沙米Agriophyllumsquarrosum,短花针茅Stipabre-viflora大量生长,草场植被盖度和生产力大幅度提高,是恢复和改良退化草场的一条行之有效的途径。

In the past few years, we have combined with the ecosystem managing engineering in the northern deserts of Gulang County in the term of the free grazing, fencing and the artificial sowing and have researched on the following items, the plant species of degenerated grassland, cover, level of the restoration succession. The results are as follows： 1）With increased time of free grazing, the ground cover of the grassland and the production ability gradually descend, the plant species gradually reduces. 2）With increased time of fencing, the ground cover of grassland and the production ability gradually increase. Species abundance increase. 3）In the condition of fencing, It quickens the speed of the grassland deterioration. 4）Fencing and artificial sowing enhance the dominant species of the desert grassland. Land sage, land rice and ephemeral plant grows largely. Grassland cover and the production ability increase. This is the method to improve and recover the deteriorated grassland.