首页|Soil water and salinity dynamics under the improved drip-irrigation scheduling for ecological restoration in the saline area of Yellow River basin
Soil water and salinity dynamics under the improved drip-irrigation scheduling for ecological restoration in the saline area of Yellow River basin
扫码查看
点击上方二维码区域,可以放大扫码查看
原文链接
NSTL
Elsevier
? 2022The drip-irrigation scheduled by different soil matric potential (SMP) thresholds at different stages according to soil water and salt management purposes was usually adopted for revegetation in saline-alkali land. To reveal the desalinization mechanism of this multi-stage drip-irrigation scheduling, a 3-year field trial, adopting this method for revegetation, was conducted in an arid saline area. The trial consisted of 5 irrigation treatments marked S1-S5, with their SMP that monitored directly under drip emitter at 0.2 m depth correspondingly controlled higher than ? 5, ? 10, ? 15, ? 20 and ? 25 kPa. Results showed the SMP threshold of ? 5 kPa during the unified irrigation stage induced a leaching fraction (LF) of 42.6% and a minimum recharge amount (MRA) from groundwater of zero, thus resulting the relative desalinization rate (RDR) of 91.8% in 0–120 cm soil layer. When treatment applied, the average electrical conductivity of the saturated soil extracts (ECe) in 0–40 cm among three growing seasons in S1-S5 treatments linearly increased from 0.90 to 1.73 dS/m as SMP threshold decreased from ? 5 to ? 25 kPa, resulting from the LF correspondingly decreasing from 18.4% to 2.5% and the MRA increasing from 0 to 21.4 mm. The inter-annual salt dynamic indicated a salt equilibrium state was formed in 80–120 cm soil layer when the SMP threshold was set higher than ? 10 kPa and that was formed in 40–80 cm soil layer if the SMP threshold was set between ? 20 and ? 15 kPa. This study found the SMP threshold controlled the LF and MRA, and eventually determined the dynamics of soil salinity, which explained the efficient desalinization mechanism under the multi-stage drip-irrigation scheduling. A key SMP threshold of ? 5 kPa for rapid soil leaching stage and that of ? 20 kPa for precise salt regulating stage were recommended for vegetation construction in the low-lying saline area.
CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone Research (YIC) Chinese Academy of Sciences (CAS) Shandong Key Laboratory of Coastal Environmental Processes YICCAS
Key Laboratory of Water Cycle and Related Land Surface Process Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences