Evapotranspiration and Quantitative Partitioning of Spring Maize with Drip Irrigation under Mulch in an Arid Region of Northwestern China

Water

Risheng Ding¹  Yanshuo Liu¹  Jie Shao¹  Chenggong Xuan¹ 

[1] Center for Agricultural Water Research in China, China Agricultural University, Beijing 100083, China;

关键词: evapotranspiration;    transpiration;    maize;    drip irrigation under mulch;    strategic deficit irrigation;   

DOI  :  10.3390/w13223169

来源: DOAJ

【 摘 要 】

To examine evapotranspiration (ET_c), soil evaporation (E_s), and transpiration (T_r), and partitioning of ET_c, a two-year field experiment was carried out in a maize field with drip irrigation under mulch in an arid region of northwestern China in 2017 and 2018. In the experiment we designed two treatments with full irrigation (T1) and growth stage-based strategic regulated deficit irrigation (T2). The applied irrigation of T2 was 40% of the T1 during both late vegetative and reproductive growth stages. Based on the measurements of soil water content (SWC) and T_r, a dual crop coefficient model (SIMDualK_c) was calibrated and validated, and daily ET_c, E_s, and T_r were estimated. The model can simulate well the dynamic variations of SWC and T_r. The calibrated basic crop coefficient at the initial, mid-season, and end growth stages was 0.2, 1.15, and 0.75, respectively. The ET_c was 507.9 and 519.1 mm for the T1 treatment, and 428.9 and 430.9 mm for the T2 treatment. The ratios of T_r to ET_c were higher for the two treatments, ~90%, for two years. Collectively, both drip irrigation under mulch and strategic deficit irrigation after canopy covering of the ground can significantly reduce the ineffective proportion of ET_c and E_s.

【 授权许可】

Unknown