关键词: 砒砂岩区, 沙棘, 平茬, 根系特征

Abstract: Aiming at the degradation of ecological function and serious soil erosion in the sandstone area of Inner Mongolia, this paper took Hippophae rhamnoides plantation as the research object, and analyzed the indexes such as root length density(RLD), growth rate(RLDgr), death rate(RLDdr) and the ratio of growth to death (Rgd)of the fine root of Hippophae rhamnoides under the conditions of the stumping group (10 cm) and non-stumping group (CK). The results showed that: ① The fine root amount of the stumping group increased in vertical space compared with CK. The fine roots of Hippophae rhamnoides in the CK were concentrated in the shallow soil layer, but the distribution of the fine roots of the stumping group in the deep soil layer increased significantly, and the distribution of the soil layer between 46 and 100 cm was more than twice that of the CK. On the whole, the growth index of the fine root of Hippophae rhamnoides after the stumping was better than the CK. ② From April to October, the RLD and RLDgr of the fine roots of Hippophae rhamnoides were a single-peak dynamic change, and reached the peak in July to August. The RLDdr of fine roots showed a trend of continuous increase, while the Rgd was contrary to the law of RLDdr. In a word, flat stubble was beneficial to improve the growth of Hippophae rhamnoides, which indirectly reflected that flat stubble was beneficial to renew and rejuvenate Hippophae rhamnoides. The results could provide scientific basis for the regeneration and rejuvenation of Hippophae rhamnoides plantations and regional ecological restoration.

Key words: sandstone area, Hippophae rhamnoides, stumping, root characteristics