Arid Zone Research ›› 2022, Vol. 39 ›› Issue (4): 1143-1154.doi: 10.13866/j.azr.2022.04.15

• Plant Ecology • Previous Articles     Next Articles

Characteristics of stem sap flow of Haloxylon ammodendron and its response to environmental factors in Qingtu Lake, Minqin

QIANG Yuquan1(),XU Xianying1,2(),ZHANG Jinchun2,LIU Hujun2,GUO Shujiang2,DUAN Xiaofeng2   

  1. 1. College of Forestry, Gansu Agricultural University, Lanzhou 730000, Gansu, China
    2. Gansu Institute of Desertification Control, Lanzhou 730000, Gansu, China
  • Received:2021-11-09 Revised:2022-03-16 Online:2022-07-15 Published:2022-09-26
  • Contact: Xianying XU E-mail:1172243258@qq.com;xyingxu@163.com

Abstract:

The daily and seasonal variation characteristics of stem sap flow of Haloxylon ammodendron with different diameters from May to October in Qingtu Lake were monitored by a TDP plug-in plant stem flow meter. Combined with meteorological data, the water consumption characteristics of Haloxylon ammodendron and its response characteristics to environmental factors were investigated. The following results are presented. (1) The diurnal variation curve of stem sap flow from June to August was mainly a single peak, and occasional multipeaks were observed in July. The peak appeared early, that is, the night sap flow was weak, and the difference between day and night was significant. From September to October, the stem fluid flow (SV) decreased significantly, and the peak time in the daily variation was delayed. On rainy days, Haloxylon ammodendron SV decreased with the increase in rainfall. (2) The stem sap flow of Haloxylon ammodendron was the largest in May, with a peak value of 291.04 cm3·cm-2·h-1. The SV of Haloxylon ammodendron increased first and then decreased from June to October and decreased sharply after reaching 225.73 cm3·cm-2·h-1 in September. (3) A large base diameter of Haloxylon ammodendron induced increased water consumption. The total water consumption of four Haloxylon ammodendron is 1988.41 kg, and the daily average water consumption is 2.76 kg, which is close to the daily average water consumption of native Haloxylon ammodendron in Gurbantunggut Desert from May to September. (4) The response of stem fluid flow of Haloxylon ammodendron to environmental factors showed substantial differences each month. The correlation degree between SV and meteorological factors on a daily scale is as follows: air temperature > net radiation > saturated water air pressure difference > relative humidity > wind speed. (3) Soil moisture has a considerable influence on Haloxylon ammodendron SV. A significant correlation was observed between soil moisture and Haloxylon ammodendron SV on sunny days, and the main area affecting Haloxylon ammodendron SV was below 100 cm of the soil layer.

Key words: Haloxylon ammodendron, meteorological factors, soil moisture, stem sap flow, Minqin