Arid Zone Research ›› 2023, Vol. 40 ›› Issue (2): 224-234.doi: 10.13866/j.azr.2023.02.07

• Plant Ecology • Previous Articles     Next Articles

Distribution and regeneration characteristics of natural Populus euphratica forests in Hexi Corridor and their relationship with soil factors

MA Junmei1,2(),MA Jianping1(),MAN Duoqing1,GUO Chunxiu1,2,ZHANG Yunian1,2,ZHAO Peng1,WANG Fei1,LI Yuanxing1   

  1. 1. Gansu Desert Control Research Institute, Lanzhou 730000, Gansu, China
    2. State Key Laboratory Breeding Base of Desertification and Aeolian Sand Disaster Combating, Wuwei 733000, Gansu, China
  • Received:2022-07-22 Revised:2022-10-11 Online:2023-02-15 Published:2023-03-08

Abstract:

A thorough investigation of the distribution of natural Populus euphratica, tree growth, regeneration characteristics, soil types, and factors in the Hexi Corridor was conducted. The distribution and regeneration status of natural P. euphratica in the Hexi Corridor, as well as its relationship with soil factors, were then examined. The results showed that: (1) Natural P. euphratica forests in the Hexi Corridor were mainly distributed in riparian terraces, ancient river terraces and the edge of oasis cultivated land in the lower reaches of Shule River, Black River, and Shiyang River. There are four main types of forest land: abandoned land, the land around cultivated fields and irrigation canals, land along the current river course, and land among ancient river course and Gobi low-lying land. (2) The growth status, age structure, and seedling regeneration of P. euphratica in the land around cultivated fields and irrigation canal, land along the current river course are better than those of the abandoned land, and among ancient river course and Gobi low-lying land. In terms of the number of renewed seedlings per unit area, the land around the cultivated field and irrigation canal was the largest, with an average value of 22.13, followed by abandoned cultivated land (20.92), land along the current river course (10.50), and among ancient river course and Gobi low-lying land (1.33). (3) Different types of P. euphratica forests have different soil factor contents: (i) Available P: In the 0-20 cm soil layer, the soil available phosphorus showed the trend as; land along the current river course < land among ancient river course and Gobi low-lying land < abandoned land, land around cultivated field and irrigation canal cultivated land; in the 20-40 cm soil layer, land along the current river course had significant less available phosphorus than the other three types of forest land (all P < 0.05); (ii) Moisture content was higher in the land around cultivated fields and irrigation canals, and land along the current river course than in abandoned land, land among ancient river course and Gobi low-lying land (all P < 0.05); (iii) In comparison to the other three types of forest land, abandoned land has significantly lower soil conductivity between the 0-20 cm and 20-40 cm soil layers (P < 0.05). There was no significant difference in the contents of total N and organic matter among different types of forest land (P > 0.05) and in the 40-60 cm soil layer, land among the ancient river course and Gobi low-lying land was significantly higher (P < 0.05). Except for the coarse sand in the 0-20 cm soil layer, the soil clay particles, silt particles, and coarse particles in the land around the cultivated field and irrigation canal performed significantly higher than those in the other three types of forest land (P < 0.05). (4) The contents of soil moisture and available P were positively correlated with the middle and young age of P. euphratica and the number of seedlings (P < 0.05). (5) To encourage the sustainable development of P. euphratica forest, improve forest management and protection, timely thinning, removal of branches and dieback, thinning, and irrigation.

Key words: Hexi Corridor, natural Populus euphratica, distribution renewal, soil factor