The Depth of Water Taken up by Walnut Trees during Different Phenological Stages in an Irrigated Arid Hilly Area in the Taihang Mountains

Forests

Xuemei Zhang¹  Guohui Qi¹  Suping Guo¹  Yang Liu¹  Shuang Zhao²  Huabing Ma³ 

[1] College of Forestry, Hebei Agricultural University, Baoding 071000, Hebei, China;Hebei Academy of Agriculture and Forestry Sciences, Shijiazhuang 050000, Hebei, China;Research Center for Walnut Engineering and Technology of Hebei, Lincheng 054300, Hebei, China;

关键词: water sources;    stable isotopes;    MixSIAR model;    walnut;    phenological stage;   

DOI  :  10.3390/f10020121

来源: DOAJ

【 摘 要 】

Understanding how the soil environment impacts root water uptake location and magnitude is important for better management of plant irrigation. In this study, stable hydrogen and oxygen isotope composition were used to determine seasonal variations in the depth of water taken up by walnut trees during different phenological stages in an irrigated arid hilly area in the Taihang Mountains in China. The contributions of soil water at different depths to the water taken up were quantified by the MixSIAR Bayesian isotope mixing model. The results indicated that water taken up by the walnut trees was sourced mainly from soil water in the 0⁻20 cm soil layer at the sprouting and leaf expansion stages (62.95%), and the 20⁻40 cm soil layer at blossoming and fruit-bearing (43.45%), fruit expansion (41.8%), and fruit maturity (39.15%) stages. The mean soil depth of the water taken up by the walnut trees gradually decreased as the phenological stages advanced. The proportions of various soil layer water contributions to the walnut trees differed throughout the phenological stages, and the proportion of deeper soil water contributions gradually increased as the phenological stages of walnut trees advanced. The results of the present study indicated that water sources for walnut trees varied by depth during different phenological stages. In addition to soil moisture, soil temperature may also be an important factor affecting the depth of water taken up by walnut trees. The results also provided scientific implications for water-saving irrigation management.

【 授权许可】

Unknown